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Citation of Electronic Information

Navigating the Citation of Electronic Information

Citation can be something of a tricky business, particularly for authors in medical fields (for whom there is no universally sanctioned style). The reliability and prevalence of online journals and databases has resulted in their near universal recognition by prominent print journals and libraries and has, consequently, lead to entirely new systems of citation. The point, of course, of any reference is to lead a reader to the source of information in as efficient a manner as possible; however, different publications require the inclusion of different pieces of information and often differ in their preference of the order and punctuation of this information. As with all forms of citation, the inclusion of references to material that is virtually inaccessible to anyone except for the author (such as personal correspondence; i.e. email) is strongly discouraged, particularly if it contains empirical data. However, referencing articles from reliable online journals and of electronic versions of articles that have also appeared in print is now a universally accepted practice.


To determine the availability of an electronic source, check to see if a journal submits its text to NLM, PubMed, or another reliable archive, or maintains its own archive of past volumes. When citing material available only online, test the validity of the web address you provide repeatedly before publication. It is important to distinguish between electronic and print versions of material available in both media, because such material is not necessarily identical and may differ, for example, in length. For your convenience, you may notice that National Library of Medicine references (and some others) include an article’s identification number in large databases such as PubMed. Some information may not be available on all web sites, but authors are encouraged to make a considerable effort to gather as much of the relevant information as possible.

Citation Guidelines
The following suggestions are based on the recommendations of the National Information Standards Organization (NISO) [as they appeared in the Wall Street Journal article on the problems of electronic citation cited below], the National Library of Medicine (NLM), the National Center for Health Statistics (NCHS), and the International Committee of Medical Journal Editors (ICMJE). Below we have included links to web sites detailing the electronic citation preferences of several style manuals (for use in the humanities, social sciences, journalism, and psychology). Citation guidelines change as frequently as the forms of information available, albeit a step behind. Naturally, an author seeking publication in a specific journal should confirm the journal’s preferences before submitting a paper.

Electronic Journal Articles
According to NISO:

Author’s last name, first name. Complete title. Journal Title [Internet]. Year month day [cited year month day]: Available from: http://etc. Subscription required.


Bell, Charlotte. MRI safety and equipment compatibility. Journal of MRI Safety [Internet]. 2005 Jun 15 [cited 2005 Jun 30]: Available from,,SB956789.html?mod=mr% Subscription required.

According to NLM:

Author’s last name, First initial. Title. Journal “[serial online]” Year Month of Publication [“cited” date cited]; Issue (Volume): [number of screens]. “Available from: URL:” url


Bell C. MRI safety and equipment compatibility. Jour MRI Saf [serial online] 2005 Jan-Mar [cited 2005 Jun 30]; 1(1): [24 screens]. Available from: URL:

Electronic Books
According to NISO

Author’s last name, first. Title [Internet]. City (state) of publication: publisher; date of publication; c copyright year [updated year month; cited year month day]. Number K bytes. Available from:


Ruskin, Keith. Anesthesiology and electronic information [Internet]. New Haven (CT): Yale University Library, Electronic Text Division; 2005; c2009 [updated 2008 Apr; cited 2010 Mar 20]. 820K bytes. Available from:

According to NLM:

Title [monograph on CD-ROM or other format]. Producers, “producers”. Edition. Version. Place of Publication: Publisher; Date of Publication.


Anesthesiology and electronic information [monograph on CD-ROM] Ruskin K, producer. 3rd ed. Version 3.0. San Diego: CMGB; 2005.

Web sites
Title [Internet]. City (state): publisher; [updated year month day; cited year month day]. Available from: http://www.etc


United States National Library of Medicine [Internet]. Bethesda (MD): The Library; [updated 2002 Apr 10; cited 2002 July 15]. Available from:

Computer Files
Title “[computer program]”. Version. Place of Publication: Publisher; Date of Publication.


Sedation VII: the ups and downs of sedation [computer program]. Version 3.6. Dallas (TX): Software Inc.; 2009.

More information

See the NCHS website for recommendations on how to cite other versions of electronic media including:

Home pages
Public-use data files
Entire databases
FTP sites
WWW sites
Telnet sites
Synchronous communications (Moos, MUDs, IRC, etc.)
Gopher sites

For further discussion of medical referencing see: The National Library of Medicine website or or the International Council of Medical Journal Editors site.