American Psychological Association, or APA, style is the format of choice for citing references, particularly in the social sciences. Increasingly, the sources used in research papers are obtained online. APA's guidelines for citing electronic sources are straightforward. The key, as with all types of references, is making certain the reader can easily access the material from the information provided.
Follow the same guidelines for citing online articles as you do when citing traditional sources, such as scholarly journal articles.
Include, if available, a volume and issue number for the online resource you are citing.
Include a Digital Object Identifier (DOI), if provided, for articles cited from an online scholarly journal. The DOI number is located on the first page of the article.
Follow the examples below, which are provided by Purdue University's Online Writing Lab.
Article from online periodical: Author, A. A., & Author, B. B. (Date of publication). Title of article. Title of Online Periodical, volume number(issue number if available). Retrieved from http://www.someaddress.com/full/URL/
Article from online-only academic journal: Author, A. A., & Author, B. B. (Date of publication). Title of article. Title of Journal, volume number. doi:0000000/000000000000
If no DOI is available, replace that with the web address.
If a scholarly article you are citing is available in print form (or came from a newspaper), use the following format:
Garcia, E. M. (2010). Writing with authority [Electronic version]. The Annals of Authoritative Writing, 21(2), 17-23.
Other Online Resources
Cite dissertations or theses found in an online database as follows: Jones, S. (1998). Essays on writing well. Retrieved from ProQuest Digital Dissertations. (AAT 22239011)
Follow this example when citing lecture notes retrieved online: Johnson, K. T. (2006). How to use APA style [PowerPoint slides]. Retrieved from http://theinternetaddress.com
Cite emails in your text as you would any other personal communication: (T. Davis, personal communication, July 18, 2010).
Use the following format to cite message board posts. If an author name is not available, use a screen name: Black Cat. (2001, June 21). How to clean oil spills [Msg 25]. Message posted to http://groups.savetheearth.org/advice