(Damrosch, et al.)
When citing the entire, multivolume work.
(Damrosch, et al, vol. C)
When citing one entire volume, but having used the entire work elsewhere.
(Damrosch, et al., C: 15-54)
When citing a page or page range of a single volume, when having used the entire work elsewhere.
Damrosch, David, et al. The Longman Anthology of World Literature. 2nd ed., Pearson Education, 2009, 6 vols.
(Damrosch, et al. 47)
The volume number is not needed because only one volume is listed on the Works Cited page.
Damrosch, David, et al. The Longman Anthology of World Literature. 2nd ed., vol. C, Pearson Education, 2009.
Include the volume number and the publication information for the single volume in the reference.
This is for situations in which only one volume was used throughout the entire paper.
(Caro 17-31)
Caro, Robert A. Master of the Senate: The Years of Lyndon Johnson III. Knopf, 2002.
If you are using only one volume of a multivolume work and the volume has an individual title, you can cite the book without reference to other volumes.