APA (7th ed.) Citation

Gaunt, L. (1977). The focalguide to lenses. Focal Press.

Chicago Style (17th ed.) Citation

Gaunt, Leonard. The Focalguide to Lenses. London ; New York: Focal Press, 1977.

MLA (9th ed.) Citation

Gaunt, Leonard. The Focalguide to Lenses. Focal Press, 1977.