APA (7th ed.) Citation

Sears, W. R. (1960). Small Perturbation Theory. Princeton University Press.

Chicago Style (17th ed.) Citation

Sears, William Rees. Small Perturbation Theory. Princeton, N.J.: Princeton University Press, 1960.

MLA (8th ed.) Citation

Sears, William Rees. Small Perturbation Theory. Princeton University Press, 1960.