Due to the ease of access to journals, electronic books and expert opinions available online, many writers find themselves citing Web sources in research papers. The sixth edition of the "Publication Manual of the American Psychological Association" establishes specific guidelines you should follow when using Internet sources in your APA writing.
In-text citations for online publications follow the same rules as those for print references: author's last name and publication year. The references entry should help your reader find that source, so a basic Web page entry begins with the author, last name followed by first initial with a comma in between. After a period, the date appears, in parentheses, with a period at the end. Then give the title of the page, capitalizing only the first word and any proper nouns, a period and "Retrieved from" -- without the quotation marks -- followed by the entire URL with no punctuation at the end. Such an entry looks like this:
Jones, K. (2013). Happiness is a bowl of peanuts. Retrieved from http://www.nuts.com/home
Electronic books follow this same format except the title of the book appears in italics if no DOI -- or Digital Object Identifier -- exists. Do not add a retrieval date unless you cite material that typically changes often, such as in a Wiki.
References page entries for online periodicals include more detail about the publication in which they appear. They start with the author, last name followed by first initial with a comma between and a period at the end. The date appears in parentheses next, followed by a period. The title of the article comes next, capitalizing the first word and proper nouns only, with a period at the end. Italicize the name of the periodical and the volume with a comma between. After a comma, give the print page numbers and a period. End the entry with the online reference such as the URL. An entry looks like this example:
Jones, K. (2013). Happiness is a bowl of peanuts. Journal of Sociology, 31, (italicized) 32-25. Retrieved from http://www.nuts.com/home
If the journal also has an issue number, put it in parentheses immediately after the volume, before the comma. For instance, 31(2) indicates volume 31, issue number 2. The issue is not italicized.
The DOI system assigns alphanumeric tags to online publications, particularly periodicals, to make them easier to find. APA requires the inclusion of the DOI in the references entry when you find one, typically at the top or bottom of the first page of an article. The DOI replaces the URL in a references page entry, following "doi:" -- without the quotation marks -- and the string. An entry looks like this example:
Jones, K. (2013). Happiness is a bowl of peanuts. Journal of Sociology, 31, (italicized) 32-25. doi: 10/8486.88609
Other kinds of sources, such as discussion or forum posts, follow slightly different structure on the references page. The entry begins with the poster's name, in inverted form just like an author if given. If not, use the screen name. After a period, give the specific date of the post in parentheses, using year-month-day order, putting a comma after the year. Place a period after the parentheses. The poster responds to an article, so type "Re:" -- without the quotation marks -- to indicate this is the subject the person was writing about followed by the name of the article or discussion. An explanation of the type of post follows in square brackets, such as [Web log comment]. The entry ends with the URL. A post reference looks like this:
Jefferson, L. (2013, April 25). Re: The nuts and the bolts of happiness and its relation to peanuts [Online forum comment]. Retrieved from http://www.nuts.com/forum/april