APA (7th ed.) Citation

Beekhuis, C. (1950). Earth cataclysms, a new theory of continental drift: A brief summary.

Chicago Style (17th ed.) Citation

Beekhuis, C. Earth Cataclysms, a New Theory of Continental Drift: A Brief Summary. [Place of publication not identified], 1950.

MLA (8th ed.) Citation

Beekhuis, C. Earth Cataclysms, a New Theory of Continental Drift: A Brief Summary. 1950.