This four page Style Sheet will provides you with examples of entries that are available at ONW. (October 2013)
The list of works cited at the end of your paper acknowledges the sources.
The author’s last name and page number used to are identify the source:
Between 1968 and 1988, television coverage of presidential elections changed dramatically (Smith 138-40).
If the author is unknown, you must use the title:
Grendel is described as a “monster living down in the darkness” (Beowulf 1-2).
If using a Web publication, or other source with no pagination, then the last name is sufficient.
In the winter the snowy owl feeds primarily on small rodents (Bloomberg).
If using a Web publication when there is no author then use the title of the work:
In the winter the snowy owl feeds primarily on small rodents (“Snowy Owl”).