[2] Greenberg, M. J., Euclidean and Non-Euclidean Geometries: Development and History, W. H. Freeman & Co. 1993.
[3] Iversen, B., Hyperbolic Geometry, Cambridge University Press 1992.
[4] Phillips, M., Gunn, C., Visualizing Hyperbolic Space: Unusual Uses for 4x4 Matrices
Created: Jul 18 1996 --- Last modified: Jul 18 1996