Cita APA (7th ed.)

Levens, A. S., & Eggers, H. C. T. (1941). Descriptive geometry. Harper.

Cita Chicago (17th ed.)

Levens, A. S., i H. C. T. Eggers. Descriptive Geometry. New York: Harper, 1941.

Cita MLA (9th ed.)

Levens, A. S., i H. C. T. Eggers. Descriptive Geometry. Harper, 1941.