Research methods unit II Scholarly Activity

40july 14 :: vol 24 no 45 :: 2010 NURSING STANDARD learning zone CONTINUING PROFESSIONAL DEVELOPMENT Aims and intended learning outcomes Although many nursing, university and medical libraries offer training in the use of bibliographic databases, Google Scholar (http://scholar.google.com) offers a pragmatic first port of call for a preliminary overview of published research in academic journals on a particular subject. Google Scholar provides access free of charge to abstracts (and sometimes the full text) of hundreds of thousands of academic journal articles, reports and other peer-reviewed publications. It is particularly useful if the nurse is not affiliated to any hospital or academic library and therefore has limited access to other bibliographic databases. The author expands on previously published continuing professional development (CPD) articles (Younger 2004, 2005) and assumes that the reader is familiar with using the internet. After reading this article and completing the time out activities you should be able to: 4Create a literature search strategy that can be used to identify relevant articles.

4Use Google Scholar to formulate and perform the search.

4Demonstrate how to limit the search.

4Understand how to expand the search.

Introduction Since the 1970s, evidence-based practice has become central to all healthcare disciplines. In a search performed in March 2010, there were 172,000 articles listed on Google Scholar for the phrase ‘evidence-based medicine’ (13,400 for 2009 alone) and 11,800 articles for the phrase ‘evidence-based nursing’ (1,270 for 2009 alone).

Healthcare staff must ensure that patient treatments and interventions are not only effective, but also that, wherever feasible and appropriate, they incorporate suggestions and evidence from recent literature and research. Finding material requires skill, time and patience, and in some cases obtaining access to bibliographic databases can be difficult. Further, depending on the subject, some databases may be more appropriate than others.

Medical Literature Analysis and Retrieval System Online (Medline) – freely available via the PubMed interface – and the Cumulative Index of Nursing and Allied Health Literature (CINAHL) are widely regarded as two of the best databases for NS551 Younger P(2010) Using Google Scholar to conduct a literature search. Nursing Standard.

24. 45, 40-46. Date of acceptance: January 25 2010.

Summary This article provides information about conducting a literature search on the Google Scholar website. The article briefly describes how to narrow or expand a search and how to find non-journal literature. Although Google Scholar is not without limitations, it offers a practical starting point for a literature search.

Author Paula Younger, library manager, North Somerset Healthcare Library, Weston General Hospital, Weston Area Health NHS Trust, Weston Super Mare. Email: [email protected] Keywords Google Scholar, internet, literature search, research methods These keywords are based on subject headings from the British Nursing Index. All articles are subject to external double-blind peer review and checked for plagiarism using automated software. For author and research article guidelines visit the Nursing Standard home page at www.nursing-standard.co.uk. For related articles visit our online archive and search using the keywords.

Using Google Scholar to conduct a literature search Page 48 Google Scholar multiple choice questionnaire Page 49 Read Stephen Minto’s practice profile on HIV and AIDS Page 50 Guidelines on how to write a practice profile p40-46 w45_LEARNING ZONE 09/07/2010 15:08 Page 40 july 14 :: vol 24 no 45 :: 2010 41 NURSING STANDARD nursing-related literature searches (Allen et al 2006). The British Nursing Index (BNI) is also good for articles on nursing and its coverage of British nursing journals is particularly strong.

However, these databases do not cover the complete range of medical and nursing material published each year.

A student attached to a university will have access to that university’s books, journals and online resources through the library. In the NHS, nurses have access to a range of online journals and other resources through the organisation’s library. To use these resources, the nurse often requires passwords and an in-depth knowledge of search techniques. In addition, each database is different, with various interfaces and subject headings, and it may be necessary to search several databases individually to ensure that as much of the available evidence as possible is returned.

Choosing Google Scholar Google Scholar can be an effective place to begin a search for published information. Like Google, it is simple to search. It differs from the main search engine in that it searches across articles, theses, books, abstracts and other academic texts only from ‘scholarly’ publications. A search on Google Scholar will return primarily peer-reviewed and academic information.

Google is the most widely used search engine, accounting for 67.3% of all internet searches worldwide (Boulton 2009). The Google Scholar interface is likely to be familiar to nurses who have used the internet, and is intuitive and uncomplicated. In addition, non-medical terms can be used to perform a search and there is no need to type in medical subject headings. Another major advantage is that the nurse does not need passwords to access abstracts with Google Scholar. However, a password or subscription may be required to access full text articles, depending on whether the nurse is accessing the internet from home, university, hospital or other institution.

The main search engine (www.google.com) remains a useful resource, particularly if thenurse knows exactly what he or she is looking for, such as the title of a report. Results from online databases such as PubMed and Google Scholar increasingly appear in standard Google searches. However, there are many academic journals that will not necessarily appear in a standard Google search, but will appear via Google Scholar. Other advantages of Google Scholar include: 4It indexes items published in peer-reviewed and academic journals. The search will be narrower than a search carried out on Google.

4It is multidisciplinary in nature, and includes content on education, management and other subjects as well as health and medicine.

Other relevant non-journal and official reports literature, notably health technology assessments and Cochrane systematic reviews, can also be identified through Google Scholar.

Literature searches Whenever there is a research question to answer, whether for an assignment, CPD or general interest, a literature search is a good place to start. This involves searching, usually on the internet, to find out who has written articles, reports and other documents on the subject. A literature search can provide the nurse with an overview of current thinking in a particular subject area. It can also highlight new ideas in areas of research and help to identify experts in a field.

Journals offer one of the most up-to-date sources of published information. However, articles usually have a delay between submission and publication (Dowding 2002), often six months to a year, and any original research will have taken place even earlier.

They are, however, more up to date than books: it usually takes one to two years for a book to be published from the submission stage (Swainson 2006).

One advantage of books and academic journals is that they have usually gone through the publisher’s editorial and quality control process. If an article or book chapter has been peer-reviewed, it has been read and commented on by experts in the author’s peer group – usually two, sometimes more – before it is published.

Where the research in the article is not clear, or improvements can be made, the reviewers will often suggest amendments or corrections. Following these comments, and subsequent author revisions, the article will then be accepted or rejected. The reader can then have reasonable confidence that the article is of sufficiently high quality to include in his or her literature search. Time out 1 Check what databases you can access from your local university, hospital or public library. Make a list of the features of two or three, for example what years and subjects they cover, and whether a password is required to log in. If full text articles are available, how easy is it to obtain them? p40-46 w45_LEARNING ZONE 09/07/2010 15:08 Page 41 42july 14 :: vol 24 no 45 :: 2010 NURSING STANDARD learning zone information technology Limitations on literature searching External factors often place limitations on the literature search. Such factors may include time limits, for example an assignment deadline or ward presentation scheduled for a particular date, limits on what full text articles can be obtained, and an assignment word count or presentation time limit.

Google Scholar, like more established bibliographic databases, also has limitations. One criticism is that it is not clear which journals are covered by Google Scholar because a source list of journal titles is not yet available (Burright 2006).

Formulating a literature search Selecting appropriate search terms is one of the keys to likely success with any database, and Google Scholar is no different. The example searches in this article focus on ‘patient dignity’ and ‘elderly care’.

Although ‘older people’ is now the preferred term, ‘elderly care’ is still used. Here it illustrates the importance of choosing appropriate search terms to retrieve as many accurate results as possible.

Many authors have discussed how to structure a literature search in general terms (Tarling and Croft 2002, Timmins and McCabe 2005, Price 2009). The basic principles are:

4Establish a clear research question. Clarify any terms that may be unclear and find synonyms for the keywords in the research question.

4Decide whether limits can be applied to the question. Use the PICO formula – breaking your research question into patient/population; intervention; comparison; and outcome (da Costa Santos et al2007) – as a framework.

The question ‘do same sex wards improve speed of recovery for older people, compared with non-same sex wards?’ formatted in the PICO framework might be: patient/population = the older people/seniors; intervention = same sex wards; comparison = non-same sex wards; and outcome = speed of recovery.

4Establish what resources might be useful and are available, for example CINAHL, PubMed and Google Scholar.

Time out 2 Consider the last time you had to perform a literature search, whether for an assignment, a ward presentation or general CPD.

Make a note of the limitations you encountered during your search. 4Perform an initial literature search.

4Examine the results to see how well the question is answered.

4Decide whether there is sufficient evidence to support or refute the argument and obtain the full text of articles that appear most relevant.

Be aware that some libraries may charge a small fee to obtain such articles.

4Restructure the search accordingly, assessing whether it needs to be refined or expanded.

Applying limits to the search Before starting the search, make a list of as many search terms as possible that might be appropriate. For ‘patient dignity’, expand this to ‘patient privacy’ or ‘patient’s dignity’, for example.

If investigating a particular patient cohort, more search terms, for example ‘elderly care’, may be required.

When constructing a search, bear in mind that the terminology may have changed in recent years: ‘geriatric’ was once a perfectly acceptable word to use, while now the more appropriate term ‘older people’ is in general use. One tip for creating ideas for keywords is to create the title of a fictional article that, if it existed, would answer the research question.

If search terms are entered within double quotation marks, the search engine will look for the terms as a phrase, resulting in fewer, but more relevant, hits.

Time out 3 Perform a search for “patient dignity” on Google Scholar, typing the words within double quotation marks. Search for patient and dignity without the speech marks or in single speech marks. What is the difference in the number of search results?

Is the article at the top of the screen still the same?

Time out 4 Carry out a Google Scholar search on a topic, for example “patient dignity”. Make a note of the number of results, listed just below the search bar on the main screen. Now run the search again, but this time put a minus sign in front of a phrase you want to exclude for example –’elderly’. How does this affect your search results? Are the results more or less accurate when it comes to answering your research question? p40-46 w45_LEARNING ZONE 09/07/2010 15:09 Page 42 july 14 :: vol 24 no 45 :: 2010 43 NURSING STANDARD A step-by-step approach To start a basic search, open an internet browser and type http://scholar.google.com in the address bar. Press ‘return’ or ‘go’. There are several different ways of searching Google Scholar. The simplest is the default option. To perform a basic search, type the search term into the large box in the middle of the screen (Figure 1), for example the phrase “patient dignity”. Other search terms, for example “elderly care”, can be added simply by typing the words into the box. The search assumes the user wishes to include all terms.

Both Google and Google Scholar use Boolean logic, as do many databases and search engines.

Boolean searching makes it easier to narrow or expand a search by putting special terms in front of the keywords. There are three main Boolean operators: ‘and’, ‘not’ and ‘or’. Google Scholar assumes ‘and’ is to be included unless otherwise specified. When searching for the words “patient dignity” and “elderly care”, Google Scholar assumes results including both sets of search terms are required.

To exclude a term use ‘not’, which in this case is a minus sign (–) in front of the word or phrase in question. So, running a search for “patient dignity” and then typing in the phrase “elderly care” with a minus sign before it (–“elderly care”) will provide fewer, but arguably more accurate, results. To widen your results, type the word ‘or’ in front of your keyword or phrase – for example “patient dignity” or “elderly care”.

Google Scholar, as with many commercial databases, also permits the use of ‘wildcards’.

This means that the database will return the stem of a word and all its variations. So, for example, to search for all variations of the term ‘family’, type in the term famil* (including the asterisk); this will return articles containing the words family, families, familiar or familial.

Advanced Google Scholar search For a more precise search, choose the Advanced Scholar Search option on the basic Google Scholar screen. It is possible either to start the search by choosing this option first, or to carry out a basic search initially, then click on the link.

In both cases, the link appears next to the button marked Search.

The advanced search screen makes the way searches are structured clearer (Figure 2). For example, transferring the previous basic search on “patient dignity” and “elderly care” into the advanced search screen reveals the phrase “elderly care” in the box marked ‘all the words’ and the phrase “patient dignity” in the box marked ‘exact phrase’. Words can also be excluded by typing them into the ‘without the words’ field. Searches can be narrowed by subject area by ticking the small square box to the left of thesubject area listings lower down the screen. For example, to limit a search to journals in the subject areas of ‘Biology, Life Sciences and Environmental Science’, and ‘Medicine, Pharmacology and Veterinary Science’, tick to the left of those choices. This will narrow the search, producing fewer results.

Results can be limited to journal articles in which the search terms appear in the title.

On the advanced search screen, click on the small downward facing arrow to the right of ‘anywhere in the article’. Click ‘in the title of the article’ and then Search Scholar. Search terms may need to be amended to obtain results, for example by removing “elderly care” from the top search box.

Search results can also be narrowed by author, although different journals may index the same author’s name in different ways. To search by author name, type the author’s name into the ‘Author’ field, for example ‘F Nightingale’.

It is also possible to narrow a search to a particular journal. In the box to the right of ‘with all of the words’ (Figure 2), type in a search term, for example “patient dignity”; then click in the box to the right of ‘Publication’ and type in either the abbreviation or the full title of the journal.

Click on Search Scholar.

Another useful feature is the option to narrow searches to particular years. The general guidance is to limit research to the previous five years, occasionally ten. To narrow the search to a particular year, click in the first small box to the right hand side of ‘Date’(Figure 2) and type in the year of interest. Leaving the right hand box on that line blank will return all articles with the specified search terms from the year specified to the most up-to-date articles. FIGURE 1 Google Scholar default search screen (basic search) Time out 5 Try searching for different combinations of an author’s name, for example ‘F Nightingale’ and ‘Florence Nightingale’. How are the results affected? p40-46 w45_LEARNING ZONE 09/07/2010 15:09 Page 43 44july 14 :: vol 24 no 45 :: 2010 NURSING STANDARD be helpful: this may appear just underneath the abstract on the left hand side of the results screen (Figure 3). Clicking this link will bring up a further list of articles, books and other items that have quoted the article.

The nurse can also use the ‘Related articles’ feature to expand a search. This will return a list of articles related to the original search – they may have similar subject terms, similar words in the title, or be by the same author. This link may be found just below each abstract on the results screen (Figure 3). In some cases, the full text of articles can be obtained immediately, whether accessing the internet from home, hospital or surgery, or if the nurse is on a university network.

In other cases, full texts may be accessible because the nurse is logged in to an organisation’s computer network or library screens, and the library has acquired an online subscription. In these cases, there may be a full text link shown in the article abstract.

In general, full text access is less likely the more recent the article, unless the library or organisation has a subscription. Articles earlier than 1995 are also rarely found online, with a small number of exceptions.

Non-journal literature Systematic reviews such as those compiled by the Cochrane Collaboration are regarded as a ‘gold The default display in Google Scholar is ten results per screen, but this can be amended to up to 100 results per screen. This and other preferences can be amended by clicking the Scholar Preferences link situated close to the box in the basic search screen (Figure 1) and adjusting the options to suit. Understanding the results A variety of results appear after the search is performed, with each abstract detailing the title of the article, the author(s), the title of the journal and the year. There is usually a short abstract detailing the article’s contents. Below the abstract, there may be information on how many other articles have cited (quoted) the article, a link to ‘Related articles’, a link either to ‘BL Direct’ (a service from the British Library for those who may not have their own library to use) or to ‘Library Search’, and links to other versions (Figure 3). If the abstract refers to a book, the phrase ‘[BOOK]’ will appear just to the left of the abstract title.

There are times when it is necessary to expand rather than narrow a search, particularly where terminology has changed or the search is highly specialised. In this case, the ‘Cited by’ feature can learning zone information technology FIGURE 2 Advanced Google Scholar search p40-46 w45_LEARNING ZONE 09/07/2010 15:09 Page 44 july 14 :: vol 24 no 45 :: 2010 45 NURSING STANDARD Google Scholar searches, relevant articles in PubMed may be incorporated into the Scholar results, allowing the nurse to click through immediately to the citation on PubMed. Such results may have an ‘ncbi.nlm.nih.gov’ link after the abstract, but will usually have ‘[CITATION]’ before the abstract title.

Clicking on a title that includes [CITATION] in Google Scholar takes the searcher through to PubMed (Figure 4). The PubMed display can be changed to Medline (click on ‘Display Settings’ on the left hand side of the screen in PubMed, then on the small circle next to ‘Medline’). The PubMed display then usually includes lines that begin with ‘MH’, standing for MeSH Heading, standard’ in terms of research. These reviews collate existing evidence on an intervention, drug, treatment or procedure and synthesise it into an authoritative and detailed summary.

Health technology assessments take a similar approach, with a particular focus on the financial effectiveness and cost benefits of a particular intervention or treatment. Both Cochrane reviews and health technology assessments are included in Google Scholar results. To search for these, type in a search term of interest, and then add the phrase “health technology assessment” or “Cochrane systematic review”, remembering to use double quotation marks. For government reports and other ‘grey’ literature, use Google rather than Google Scholar. Assessing the results of the search Once articles have been discovered, they need to be analysed in terms of whether they address the research question. The nurse will not have sufficient time to perform a detailed critical appraisal of all articles, but asking the questions listed below can help with the decision whether to include or exclude an article in the review:

4Is it a quantitative article (mainly analysing numerical responses) or is it qualitative (analysing the results of surveys, interviews and open questionnaire questions)?

4How thorough is the research?

4How recent is the research?

4How large was the sample size?

4What are the author’s credentials?

Other uses of Google Scholar There are times when a literature search on Google Scholar, however skilful, will benefit from supplementary searches on other specialised databases such as PubMed, BNI and CINAHL, if access to the latter two is available. These databases may offer different full text articles from those available via Google Scholar.

A useful way of putting Google Scholar results to work in broadening results is to take keywords from the titles or author names in the articles and search for these terms in a major nursing or medical database, for example PubMed. On FIGURE 3 Understanding your results Time out 6 Take one of the articles that you have found and obtain the full text. Answer the questions above to briefly appraise the article. FIGURE 4 PubMed search screen p40-46 w45_LEARNING ZONE 09/07/2010 15:09 Page 45 46july 14 :: vol 24 no 45 :: 2010 NURSING STANDARD Completion of the literature search It is difficult to ascertain when a literature search is complete. Likely indicators that the literature search is coming to an end might include:

4Repeatedly obtaining the same articles in search results.

4Lack of any new information in the last few searches.

4When the nurse feels that he or she has sufficient evidence to support the research, assignment or presentation.

Conclusion Like Google, Google Scholar is an excellent way to begin a literature search. It offers a preliminary method of gathering basic information about what has been written on a particular subject area. This can then be used to form the basis of a more detailed search on specialised databases: such a search is essential when conducting more complex and in-depth literature reviews and systematic reviews.

Acknowledgement Google Scholar™ screenshots have been used in accordance with Google permissions at www.Google.co.uk/permissions/index.html learning zoneinformation technology which gives details of the main subjects of an article. Using MeSH headings as additional keywords for further searches can help to ensure that a search is comprehensive: titles do not always describe article contents accurately.

One other way of searching Google Scholar is to search for the local hospital, trust or organisation. This will provide an overview of local colleagues who have published articles in journals.

Disadvantages of Google Scholar No database is perfect or comprehensive, and Google Scholar is no exception. For some journal collections, a separate search may be required.

Not all journals are indexed on Google Scholar, hence the search using that journal name would return no results. Some aspects of the Google Scholar search remain unclear: for example results do not necessarily appear in order of relevance or date of publication.

Other limitations include the fact that, at present, unlike some of the commercial and longer-established databases such as PubMed or CINAHL, it is not possible to select more than one journal article at a time to copy into a word processing programme or export to reference software, nor can the search be limited to specific volume and issue numbers. The Google Scholar database is, however, still at the testing stage and has already improved dramatically: further improvements undoubtedly lie ahead. Time out 7 Now that you have completed the article, you might like to write a practice profile. Guidelines to help you are on page 50. Allen MP, Allison MM, Stevens S (2006) Mapping the literature of nursing education. Journal of the Medical Library Association. 94, Suppl 2, E122-E127.

Boulton C(2009) Google Worldwide Search Share Slips a Tad as Queries Soar.

http://bit.ly/9dR9w0 (Last accessed: July 1 2010.) Burright M(2006) Google Scholar – Science and Technology. www.istl.org/ 06-winter/databases2.html (Last accessed: July 1 2010.) da Costa Santos CM, de Mattos Pimenta CA, Nobre MR(2007) ThePICO strategy for the research question construction and evidence search. Revista Latino-Americana de Enfermagem. 15, 3, 508-511.

Dowding K(2002) Publishing in Academic Journals. http://bit.ly/bhKRWV (Last accessed: July 1 2010.).

Price B,(2009) Guidance on conducting a literature search and reviewing mixed literature. Nursing Standard. 23, 24, 43-49.

Swainson B(2006) Understanding the Publishing Process. http://bit.ly/cJ9FO9 (Last accessed: July 1 2010.)Tarling M, Croft L (Eds)(2002) The Essential Researcher’s Handbook for Nurses and Health Care Professionals.

Second edition. Baillière Tindall, Edinburgh.

Timmins F, McCabe C(2005) How to conduct an effective literature search.

Nursing Standard. 20, 11, 41-47.

Younger P(2004) Using the Internet to conduct a literature search. Nursing Standard. 19, 6, 45-51.

Younger P(2005) The effective use of search engines on the Internet. Nursing Standard. 19, 48, 56-64.

References p40-46 w45_LEARNING ZONE 09/07/2010 15:09 Page 46 48july 14 :: vol 24 no 45 :: 2010 NURSING STANDARD 9. What do health technology assessments aim to do?

a) Inform on the financial effectiveness of interventions ❏ b) Inform on the cost benefits of interventions ❏ c) Provide an authoritative summary of the evidence ❏ d) All of the above ❏ 10. When might a literature search be finished?

a) When the same results keep appearing ❏ b) When no new information appears in searches ❏ c) When there is enough evidence for the assignment ❏ d) All of the above ❏ This self-assessment questionnaire was compiled by Ed Rowe The answers to this questionnaire will be published on July 28 1. How many articles did Google Scholar list for the phrase ‘evidence-based medicine’?

a) 152,000 ❏ b) 162,000 ❏ c) 172,000 ❏ d) 182,000 ❏ 2. Which database might be used to search articles on nursing?

a) Medline ❏ b) International Nursing Index ❏ c) British Nursing Index ❏ d) All of the above ❏ 3. What does peer review involve?

a) Comments on a journal article from an author’s peers ❏ b) Editorial amendments to an article ❏ c) Acceptance of a journal article ❏ d) Rejection of a journal article ❏ 4. Google Scholar:

a) Searches on the main Google search engine ❏ b) Includes ‘grey’ literature ❏ c) Is a specialist medical database ❏ d) Lists items published in peer reviewed and academic journals ❏ 5. Typing ‘AND’ between two search phrases in Google Scholar will:

a) Bring back results for one phrase, but not the other ❏ b) Bring back fewer results ❏ c) Bring back more results ❏ d) Make no difference ❏ 6. General guidance for literature searches is often to limit results:

a) To the previous 5 years ❏ b)To the previous 7.5 years ❏ c) To the previous 12.5 years ❏ d)To the previous 15 years ❏ 7. What does the ‘Cited by’ link in Google Scholar provide?

a) Related articles ❏ b) Articles on PubMed ❏ c) A list of publications that have quoted the article ❏ d) A list of authors ❏ 8. What is a quantitative article concerned with?

a) Facts and figures ❏ b) Patient interviews ❏ c) Surveys ❏ d) Responses to open questionnaires ❏ learning zone assessment Google Scholar TEST YOUR KNOWLEDGE AND WIN A £50 BOOK TOKEN HOW TO USE THIS ASSESSMENT This self-assessment questionnaire (SAQ) will help you to test your knowledge. Each week you will find ten multiple-choice questions that are broadly linked to the learning zone article.Note: There is only one correct answer for each question.

Ways to use this assessment 4You could test your subject knowledge by attempting the questions before reading the article, and then go back over them to see if you would answer any differently.

4You might like to read the article to update yourself before attempting the questions.

Prize draw Each week there is a draw for correct entries.

Please send your answers on a postcard to: Zena Latcham, Nursing Standard, The Heights, 59-65 Lowlands Road, Harrow-on-the-Hill, Middlesex HA1 3AW, or send them by email to:

[email protected] Ensure you include your name and address and the SAQ number. This is SAQ no. 551.

Entries must be received by 10am on Tuesday July 27 2010.

When you have completed your self-assessment, cut out this page and add it to your professional portfolio. You can record the amount of time it has taken. Space has been provided for comments.

You might like to consider writing a practice profile, see page 50. Report back This activity has taken me ____ hours to complete.

Other comments:

Now that I have read this article and completed this assessment, I think my knowledge is:

Excellent ❑ Good ❑ Satisfactory ❑ Unsatisfactory ❑ Poor ❑ As a result of this I intend to:

Answers to diuretic therapy questions The answers to SAQ no. 549 on diuretic therapy, which appeared in the June 30 issue, are:

1. c 2. d 3. b 4. c 5. a 6. b 7. d 8. a 9. d 10. a p48 w45_Assessment 09/07/2010 15:03 Page 48 Copyright of Nursing Standard is the property of RCN Publishing Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission.

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