ABSTRACT
Tomazˇ Pisanski, University of Ljubljana, Slovenia
Primozˇ Potocˇnik, University of Ljubljana, Slovenia
7.1.1 Surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 730
7.1.2 Polygonal Complexes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 736
7.1.3 Imbeddings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 738
7.1.4 Combinatorial Descriptions of Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 741
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 744
INTRODUCTION
The need to imbed (draw) finite graphs on surfaces arises in various aspects of mathematics and science. Often the simplest surface in which such a graph can be imbedded is sought. Some generalizations of surfaces are briefly considered.