For a source with three or fewer authors, list the authors' last names in the text or parenthetical citation:
Hamilton, Lorice, and Todd argue that tougher gun control is not needed in the United States (76).
The authors state "Tighter gun control in the United States erodes Second Amendment rights" (Hamilton, Lorice and Todd 76).
For a source with three or more authors, use the first author's last name followed by et al. or put all the last names:
Soltau et al. counter Hamilton, Lorice and Todd's argument by noting the current spike in gun violence in the United States (4).
Another author counters Hamilton, Lorice and Todd's argument by noting the current spike in gun violence in the United States (Soltau et al. 4).
Wordsworth stated that Romanic poetry was marked by a "spontaneous overflow of powerful feelings" (263).
Romantic poetry is characterized by the "spontaneous overflow of powerful feelings" (Wordsworth 263).
Wordsworth extensively explored the role of emotion in the creative process (263).
Wordsworth, William. Lyrical Ballads. London: Oxford University Press, 1967. Print.
When a source has no author, use a shortened title of the work instead. Place the title in quotation marks if its a short work (article) or italicize it if it's longer (plays, books, entire websites) and provide a page number.
We see so many global warming hotspots, because this region has "more readily accessible climatic data" ("Impact of Global Warming" 6).
"The Impact of Global Warming in North America." Global Warming: Early Signs. 1999. Web. 14 Dec. 2011.