1. Beardon, A. F., Geometry of Discrete Groups, Springer Verlag 1983., 1983.
2. Buseman, H. and P. J. Kelly, Projective Geometry and Projective Metrics, Academic Press, 1953.
3. von Brzeski, J. G. and V. von Brzeski, "Intensity and polarization of light in Lobachevskian space," In preparation..
4. Chernikov, N. A. and Preprint No. 723, Joint Institute for Nuclear Research (JINR) Dubna, No. Preprint 723, 1961 (in Russian)., 1961.
5. Chernikov, N. A., Doklady Academy of Sciences of USSR, 114, 1957.
6. Gelfand, I. M., M. I. Grayev, and N. Ya. Vilenkin, Generalized Functions, Vol. 5, Vol. 5, 1966.
7. Heintze, E. and H. Christoph, "Geometry of horospheres," J. Differential Geometry, Vol. 12, 481-491, 1997.
8. Helgason, S., "Geometric analysis on symmetric spaces," Math. Surveys and Monographs, Vol. 39, 1994.
9. Klein, F., Vorlesungen uber Nicht Euklidische Geometrie, AMS Chelsea Publishing, 2000.
10. Rosenfeld, B. A., A History of Non Euclidean Geometry, Springer Verlag, 1988.
11. Smorodinsky, Ya. A., "Kinematics and Lobachevskian geometry," Atomnaya Energia, Vol. 14, 1963.
12. Sternberg, S., Group Theory and Physics, Cambridge University Press, 1995.