APA (7th ed.) Citation

Beckmann, P. (1971). A history of π (pi). St. Martin's Press.

Chicago Style (17th ed.) Citation

Beckmann, Petr. A History of π (pi). New York: St. Martin's Press, 1971.

MLA (8th ed.) Citation

Beckmann, Petr. A History of π (pi). St. Martin's Press, 1971.