APA (7th ed.) Citation

Welford, W. T. (1974). Aberrations of the symmetrical optical system. Academic Press.

Chicago Style (17th ed.) Citation

Welford, W. T. Aberrations of the Symmetrical Optical System. London ; New York: Academic Press, 1974.

MLA (9th ed.) Citation

Welford, W. T. Aberrations of the Symmetrical Optical System. Academic Press, 1974.