APA (7th ed.) Citation

Sommerfeld, A. (1923). Atomic structure and spectral lines. Dutton.

Chicago Style (17th ed.) Citation

Sommerfeld, Arnold. Atomic Structure and Spectral Lines. New York: Dutton, 1923.

MLA (8th ed.) Citation

Sommerfeld, Arnold. Atomic Structure and Spectral Lines. Dutton, 1923.