Rich, B. (1963). Principles & problems of plane geometry. Schaum Pub. Co.
Lua i Stíl Chicago (17ú heag.)Rich, Barnett. Principles & Problems of Plane Geometry. New York: Schaum Pub. Co, 1963.
Lua MLA (9ú heag.)Rich, Barnett. Principles & Problems of Plane Geometry. Schaum Pub. Co, 1963.
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