APA (7th ed.) Citation

Humphreys, R. F., & Beringer, R. (1950). First principles of atomic physics. Harper.

Chicago Style (17th ed.) Citation

Humphreys, Richard F., and Robert Beringer. First Principles of Atomic Physics. New York: Harper, 1950.

MLA (9th ed.) Citation

Humphreys, Richard F., and Robert Beringer. First Principles of Atomic Physics. Harper, 1950.