APA (7th ed.) Citation

Tinker, G., & Tinker, B. (1968). Let's learn to snorkel. Walker.

Chicago Style (17th ed.) Citation

Tinker, Gene, and Barbara Tinker. Let's Learn to Snorkel. New York: Walker, 1968.

MLA (9th ed.) Citation

Tinker, Gene, and Barbara Tinker. Let's Learn to Snorkel. Walker, 1968.