The third edition of the "MLA Style Manual and Guide to Scholarly Publishing" offers information on style and format for the liberal arts and humanities. Rules for citing references are included for traditional sources such as books as well as alternative material, including press releases.
When including information from a source, use an in-text citation. Do this in one of two ways. Mention the name of the organization releasing the material in the text, or place the name inside parentheses after the information, such as: (The Theater Group).
Any source mentioned in text must be put on the Works Cited page at the end. A citation for a press release is similar to that for a book. Start with the name of the organization releasing the information and follow this with a period. Next comes the italicized name of the press release in title case. Add a period. Follow with the publication location, a colon, the publisher -- often the organization releasing the info -- a comma, the publication date, month, year and a period. At the end, indicate the type of media, such as "Print," without quotation marks; for example: The Theater Group. Upcoming Shows for the 2013 Season. New York: The Theater Group, 14 Jan. 2013. Print.