Many written sources, such as compiled books and scholarly journals, are published over multiple volumes. In American Psychological Association style, a short note of the volume information for a source is included in that source's reference list citation.
Books With Volumes
A book published in multiple volumes includes the volume information after the title on your reference list citation. The APA reference list style for a book is as follows:
Author Lastname, First Initial(s). (Year). Title of book: Subtitles if applicable* (Vol. Number). Publication Location: Publisher Name.
Here's an example:
Colm, R. (1994). Theories of research (Vol. 2). New York, NY: Random House.
If you reference multiple volumes of the same book in your paper, list all included volumes in your citation:
Dion, J. (2001). Collections of information: A qualitative perspective (Vols. 1-5). Chicago, IL: The University of Chicago Press.
If your reference list includes an article taken from a periodical, the volume and issue number of journal are included on the reference list. This format is used for periodical articles in APA:
Author Lastname, First Initial(s). (Year, Month and Day if applicable). Title of article: Subtitle of article. Title of journal, volume number (issue number), pages of article.
As an example:
Gunnerson, L. (1989, February). The muskie and the walleye. Thousand Lakes fishing monthly, 18 (2), 12-17.
A work with volumes is not cited differently than other works in the body of your text. Include the author number, year of the work and the page number of the cited information, if applicable:
The postmodern predicament does not extend into the "methods qua methods," the "physical grounding of research" (Colm, 1994).