1. Bennett, M. K. and G.Birkhoff. A Peano Axiom for Convexity Lattices. To appear in the Bulletin of the Calcutta Math. Soc., 75th Jubilee Issue, September 1983.
2. Bennett, M. K. On generating affine geometries. Alg. Univ. 4 (1974) 207?219.
3. Dubreil-Jacotin, M. L., L. Lesieur, andB. Croisot,Le�ons sur la Th�orie des Trellis. Paris, Gauthier Villars, 1953.
4. Gr�tzer, G. General Lattice Theory, New York. Academic Press, 1978.
5. Hilbert, D. Foundations of Geometry. (Transl. by E. J. Townsend) La Salle, Open Court, 1902.