Lockwood, J. R., & Runion, G. E. (1978). Deductive systems: Finite and non-euclidean geometries. National Council of Teachers of Mathematics.
Chicago-referens (17:e uppl.)Lockwood, James R., och G E. Runion. Deductive Systems: Finite and Non-euclidean Geometries. Reston, VA: National Council of Teachers of Mathematics, 1978.
MLA-referens (9:e uppl.)Lockwood, James R., och G E. Runion. Deductive Systems: Finite and Non-euclidean Geometries. National Council of Teachers of Mathematics, 1978.
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