Webpages and websites are sometimes the most confusing sources to cite. Magazine, journal, and newspaper articles are all found on the web; in those cases, citations will be similar to the print versions of these items. Sometimes, however, the content on a webpage does not fit into one of those categories - the content may simply be information on a page. In cases like these, you need to think about the four W's:
Just remember that regardless of format, APA instructs that you gather those four pieces of information.
APA full citation:
U.S. National Library of Medicine, MedlinePlus. (2012). Imaging and radiology. Retrieved from http://www.nlm.nih.gov/medlineplus/ency/article/007451.htm
In this example:
Valencia Library has created APA cheat sheets and made them available online. Review our APA examples for websites.