\input zb-basic \input zb-matheduc \iteman{ZMATH 1997b.01252} \itemau{Erickson, M.J.} \itemti{Introduction to combinatorics.} \itemso{Wiley, New York, NY (ISBN 0-471-15408-3). 207 p. (1996).} \itemab The gradual, systematic introduction to the main concepts of combinatorics is a text for advanced undergraduate and early graduate courses in this subject. Each of the book's three sections - existence, enumeration, and construction - begins with a simply stated first principle, which is then developed step by step until it leads to one of the three major achievement of combinatroics: Van der Waerden's theorem on arithmetic progressions, Polya's graph enumeration formula, and Leech's 24-dimensional lattice. Along the way, the author introduce fundamental results, discusses interconnection and problem-solving techniques, and collects and disseminates open problems that raise new and innovative questions and observations. The end-of-chapter exercises demonstrate the applicability of combinatorial methods to a wide variety of problems, including many drawn from the William Lowell Putnam Mathematical Competition. Many important combinatorial methods are revisited several times - in exercises and examples as well as theorems and proofs. \itemrv{~} \itemcc{K20} \itemut{} \itemli{} \end