Posamentier, A. S., & Salkind, C. T. (1996). Challenging problems in geometry. Dover Publications.
Chicago Style aipamenaPosamentier, Alfred S., and Charles T. Salkind. Challenging Problems in Geometry. New York: Dover Publications, 1996.
MLA aipamenaPosamentier, Alfred S., and Charles T. Salkind. Challenging Problems in Geometry. Dover Publications, 1996.
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