APA (7th ed.) Citation

Sommerfeld, A., Bopp, F., & Meixner, J. (1956). Lectures on theoretical physics. Academic Press.

Chicago Style (17th ed.) Citation

Sommerfeld, Arnold, F. Bopp, and J. Meixner. Lectures on Theoretical Physics. New York: Academic Press, 1956.

MLA (9th ed.) Citation

Sommerfeld, Arnold, et al. Lectures on Theoretical Physics. Academic Press, 1956.