APA (7th ed.) Citation

Crichton, M. (1991). Sphere: A novel (15. print.). Ballantine Books.

Chicago Style (17th ed.) Citation

Crichton, Michael. Sphere: A Novel. 15. print. New York: Ballantine Books, 1991.

MLA (9th ed.) Citation

Crichton, Michael. Sphere: A Novel. 15. print. Ballantine Books, 1991.