On Citing Electronic Sources

Materials obtained electronically need to be cited differently from those obtained directly from print sources. The Electronic Reserves staff has neither the time nor the resources to provide instruction on citing electronic sources, and we ask that you consult the appropriate style manual for more information. The recent editions of most common style guides include formats for citing various types of online resouces*, including full text databases, online serials, Web sites, — even retrievable forum and newsgroup postings. The the most recent editions of the most commonly referenced manuals are:

• The Chicago Manual of Style, 15th ed. Chicago: U of Chicago P, 2003. [Call No.: Z253 .U69 2003]**
• Publication Manual of the American Psychological Association, 5th ed. Washington, DC: American Psychological Association, 2001. [Call No.: BF76.7 .P83 2001]**
• MLA Handbook for Writers of Research Papers, 6th ed. New York: Modern Language Association of America, 2003.

If for any reason you do not have access to your style manual, the following links can be used to find examples for the most common situations.

• "Big Four" (Chicago/Turabian, APA, MLA, CBE*):
  • Citation Styles @ NIU English Dept. (Collection of external links)
  • Research and Documentation Online by Diana Hacker (Recommended by Electronic Reserves staff)
  • ONLINE! Citation Styles by Andrew Harnack and Eugene Kleppinger
• Anthropolgy:
  • AAA Style Guide
  • ASA Style Guide
• Other:
  • AMA Citation Style
  • Basic Legal Citation (LII 2003 ed.) by Peter W. Martin
  • National Library of Medicine Recommended Formats for Bibliographic Citation Supplement: Internet Formats

*The sixth edition of Scientific Style and Format: The CBE Manual for Authors, Editors, and Publishers does not contain information on citing Internet sources. A seventh edition is in progress, and in the meantime the Council of Science Editors' recommendation is to refer to the National Library of Medicine (NLM) format.

**Call numbers refer to books at Founders' Memorial Library.

Anatomy of a URL

When referencing an Internet source, a URL (a Web address) is often needed. Below is a example URL, broken down into four common parts:

1. protocol: HTTP is the most common protocol for the the Web; you might also run into FTP or, very rarely, gopher. Always leave the protocol in the URL when you are citing.
2. domain name: This is the unique name of the Web site, or at least the Web site's host. Sometimes when you are citing a document that does not have a stable URL, the protocol and the domain name are all you need to include.
3. path: Documents on the Web are organized much like files on your computer, in a series of named, nested directories (or "folders"). The text between the slashes (/) are, generally, the names of these directories.
4. file: You will not alway see a file name at the end; if you do not, it is likely "index.html". Most documents on the web have the file extension *.html or *.htm. Very often, however, you may be referencing a *.pdf or *.txt file. Some documents do not have a file extension at all. When you are citing a document with a direct, stable URL, make sure that your URL directs the reader to that document, and not a referring document, no matter what file extension is.

When is a URL "stable"?

Sometimes when referencing electronic sources, you need to be able to determine whether or not a URL is stable. Look at the URL below:

http://www.virtualtoychest.com/swampthing/swampthing.html

This URL gives the exact location of the file swampthing.html at the domain www.virtualtoychest.com . So long as this file remains where it is, this URL can be called stable. A stable URL will be an easily recognizable path to a file, the only characters being letters (a-z and A-Z), digits (0-9), periods, slashes (/), and sometimes tildes (~), hyphens (-) and underscores (_). Compare that to the next URL:

http://web15.epnet.com/citation.asp?tb=1&_ug=sid+459A5311%2D68DA%2D4EBA%2D95EE
%2DACA87F5A7693%40sessionmgr3+dbs+afh%2Crih+cp+1+9247&_us=hs+False+or+Date+ss+
SO+sm+KS+sl+%2D1+ri+KAAACBXB00000353+dstb+KS+mh+1+frn+11+BA84&_uso=hd+False+tg
%5B0+%2D+st%5B0+%2Dswamp++thing+db%5B1+%2Drih+db%5B0+%2Dafh+op%5B0+%2D+7736&fn
=11&rn=20

This URL was generated by searching a term in EBSCO Academic Search Elite. Some thing to notice about the URL:

• It is longer than average.
• It contains characters like ?&=+% and random-seeming letters and numbers.

The actual filename of this document is citation.asp . But the content of the document is generated by the code that comes after the question mark, code that contains details of the search that was performed: a "session id," search terms, database name, etc. Because this code refers to one specific searching session, if you were to copy the URL into an address bar you would get an error message saying, "Your session has expired. To begin a new session, please login again." This URL is not stable. You should not include a URL like this with a citation; instead you should include the name of and/or URL for the database, as the documentation style requires.

Many databases provide what they call a "stable" or "persistent" URL within the database's short description of the article (i.e. not in the address bar). The following would retrieve the record searched for in the last example:

http://search.epnet.com/login.aspx?direct=true&db=afh&an=8907100316

This URL will always retrieved the record in question, no matter where it is moved to. Whether or not this can be used in a citation depends on the citation style.