Anthologies are collections of multiple works either by the same author or organized around the same theme. How you cite an anthology in the seventh edition of the American Psychological Association (APA) style depends on whether you are citing the entire anthology or a specific work within it.
An entire anthology/edited book
Treat the editor of the anthology as its author, i.e. Editor's Last Name, First Initials. (Eds.). (Year of Publication). Title of book. Publisher.
Example Citation
Potter, P. A., Perry, A. G., Kerr, J. C., & Wood, M. J. (Eds.). (2009). Canadian fundamentals of nursing. Mosby/Elsevier Canada.
A single work included in the anthology/edited book
Place the author of the work first, and include information about the editor of the anthology later in the citation, i.e. Author’s Last Name, First Initials. (Year of anthology’s publication). Title of work in anthology. In First Initial. Last Name of the anthology editor (Ed.), Title of anthology (page numbers). Publisher.
Example Citation
Blake, W. (1990). The Tyger. In R. Scholes, N. R. Comley, C. H. Klaus, & D. Staines (Eds.), Elements of literature (pp 487-488). Oxford University Press.
Pen and the Pad has a good explanation of these citations.