Table of Contents

Preface 1 The Functions of Schlafli and Lobatschefsky 2 Integral Cayley Numbers 3 Wythoff's Construction for Uniform Polytopes 4 The Classification of Zonohedra by Means of Projective Diagrams 5 "Regular Skew polyhedra in Three and Four Dimensions, and Their Topological Analogues " 6 Self-dual Configurations and Regular Graphs 7 "Twelve Points in PG(5, 3) with 95040 Self-transformations " 8 Arrangements of Equal Spheres in Non-Euclidean Spaces 9 An Upper Bound for the Number of Equal Nonoverlapping Spheres That Can Touch Another of the Same Size 10 Regular Honeycombs in Hyperbolic Space 11 Reflected Light Signals 12 Geometry Index