Birkhoff, G. D., & Beatley. (1963). Basic geometry: Answer book. [s.l.]: Chelsea Publishing Company.
Παραπομπή Chicago StyleBirkhoff, George David, and Beatley. Basic Geometry: Answer Book. [s.l.]: Chelsea Publishing Company, 1963.
Παραπομπή MLABirkhoff, George David, and Beatley. Basic Geometry: Answer Book. [s.l.]: Chelsea Publishing Company, 1963.
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