Cite the material in MLA style. Begin the citation with the title of the work. If a date is present, include a date. For example: "Taken by Surprise." Yahoo. Web. 15 Dec. 2010." If the date is not present, cite "(N.d.)." in place of the date.
List your source in Chicago style. Start the citation with the title of the document, leaving off the author name and following the rest of the reference in traditional Chicago style. If the document is online, cite the date you found the document. For example Guinea pigs. Retrieved April 17, 2011, from http://www.guineapigssite.com/guineapigs.
Reference the citation in APA style. Place the title of the work at the beginning of the citation, where the author name would usually be placed. Follow the rest of the citation in standard APA style. For example: Taking on giants. (2010). Encyclopedia of Everyday Heroes, 27-39.