APA (7th ed.) Citation

Lewis, C. S., & Hooper, W. (1982). Of this and other worlds. Fount Paperbacks.

Chicago Style (17th ed.) Citation

Lewis, C. S., and Walter Hooper. Of This and Other Worlds. London: Fount Paperbacks, 1982.

MLA (9th ed.) Citation

Lewis, C. S., and Walter Hooper. Of This and Other Worlds. Fount Paperbacks, 1982.