群的上同调

《群的上同调》讲述了：This book is based on a course given at Cornell University and intendedprimarily for second-year graduate students. The purpose of the course wasto introduce students who knew a little algebra and topology to a subject inwhich there is a very rich interplay 'between the two. Thus I take neither apurely algebraic nor a purely topological approach, but rather I use bothalgebraic and topological techniques as they seem appropriate The first six chapters contain what I consider to be the basics of the subjectThe remaining four chapters are somewhat more specialized and reflect myown research interests. For the most part, the only pre'requisites for readingthe book are the elements of algebra （groups, rings, and modules, includingtensor products over non-commutative rings） and the elements of algebraictopology （fundamental group, covering spaces, simplicial and CW-complexes, and homology）. There are, however, a few theorems, especially inthe later chapters, whose proofs use slightly more topology （such as theHurewicz theorem or Poincare duality）.