APA (7th ed.) Citation

Norton, A., & Dickson, G. R. (1956). The crossroads of time. Ace Books.

Chicago Style (17th ed.) Citation

Norton, Andre, and Gordon R. Dickson. The Crossroads of Time. New York, N.Y.: Ace Books, 1956.

MLA (8th ed.) Citation

Norton, Andre, and Gordon R. Dickson. The Crossroads of Time. Ace Books, 1956.