• Ebooks need some extra information in their citations, just as e-articles do.
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• RefWorks will pull citations from the library catalog or article database, but you must still add the extra information to show that you used an electronic source

APA = American Psychological Association

Note that APA style requires you to add the type of e-device, where you retrieved the ebook, and the URL or doi.

• Gladwell, M. (2008). Outliers: The story of success [Kindle DX version]. Retrieved from Amazon.com

• Shotton, M.A. (1989) Computer addiction? A study of computer dependency [DX Reader version]. Retrieved from http://www.ebookstore.tandf.co.uk/html/index.asp]

• Brill, P. (2004). The winner’s way [Adobe Digital Editions version]. doi:10.1036/007142363X

Here is more information about APA style, including the APA Style Blog, which you can search for more information about citing electronic things.

MLA = Modern Language Association

The MLA understands that the world of citing electronic information is fluid (phone call, April 21, 2011).

Usually, you can use the style for citing a print book and then just add the additional information to indicate its electronic origin and when you accessed it, as shown below.

The point to remember is to include enough information for others to be able to find your source.

Book available only on the web or downloaded to an e-device

• Author or Editor’s Last Name, First Name. Title of Book [put in quotes if part of a book]. Title of the Website. Editor of website [if given]. Publisher or sponsor of site [or N.p. if not available], Date of electronic publication [or N.d. if not available]. Medium [e.g., Web]. Day Month year of access.

• Wilde, Oscar. The Picture of Dorian Gray. Project Gutenberg. N.p. (because I don't know the publisher) N.d. (because I don't know the date of electronic publication) EPUB. (or Nook Color, or Digital File, if you don't know the format) Downloaded March 25, 2011.

Book that has been scanned and put on the web (e.g., from Google Books or from The Complete Works of Charles Darwin Online)

• Powers, Robert. War Stories: A Sailor Remembers the Vietnam War. Historical Text Archive. Ed. Donald J. Mabry. N.p., 2006. Web. 25 Mar. 2011.
• Child, L. Maria, ed. The Freedmen's Book. Boston, 1866. Google Book Search. Web. 15 May 2008. 
  
  [this example is in MLA Handbook of Writers of Research Papers, 7th ed., section 5.6.2, "A work cited on the web with print publication data"]

See also the online example from the source below: