Greenberg, M. J. (1980). Euclidean and Non-Euclidean Geometries: Development and history (2nd ed.). W. H. Freeman and Co..
Cita Chicago (17th ed.)Greenberg, Marvin Jay. Euclidean and Non-Euclidean Geometries: Development and History. 2nd ed. New York: W. H. Freeman and Co., 1980.
Cita MLA (9th ed.)Greenberg, Marvin Jay. Euclidean and Non-Euclidean Geometries: Development and History. 2nd ed. W. H. Freeman and Co., 1980.
Atenció: Aquestes cites poden no estar 100% correctes.