APA (7th ed.) Citation

Beyer, R. T., & Letcher, S. V. (1969). Physical ultrasonics. Academic Press.

Chicago Style (17th ed.) Citation

Beyer, Robert T., and Stephen V. Letcher. Physical Ultrasonics. New York,: Academic Press, 1969.

MLA (8th ed.) Citation

Beyer, Robert T., and Stephen V. Letcher. Physical Ultrasonics. Academic Press, 1969.