Παραπομπή APA

Posamentier, A. S., & Salkind, C. T. (1996). Challenging problems in geometry. Dover Publications.

Παραπομπή Chicago Style

Posamentier, Alfred S., και Charles T. Salkind. Challenging Problems in Geometry. New York: Dover Publications, 1996.

Παραπομπή MLA

Posamentier, Alfred S., και Charles T. Salkind. Challenging Problems in Geometry. Dover Publications, 1996.