APA (7th ed.) Citation

Fletcher, M. P., & Thorson, J. L. (1989). Reader's guide to twentieth-century science fiction. American Library Association.

Chicago Style (17th ed.) Citation

Fletcher, Marilyn P., and James L. Thorson. Reader's Guide to Twentieth-century Science Fiction. Chicago, IL: American Library Association, 1989.

MLA (9th ed.) Citation

Fletcher, Marilyn P., and James L. Thorson. Reader's Guide to Twentieth-century Science Fiction. American Library Association, 1989.