Allen Hatcher is a professor of mathematics at Cornell University. On his home page, he offers a link to download his book Algebraic Topology in its entirety. Published in 2002, the book is over 500 pages in length and is free to anyone wanting a personal copy. In addition to Algebraic Topology, there are three other books that are work-in-progress. Despite being incomplete, they could be useful to students in related classes. Several research papers written by Professor Hatcher are also given on this site.
(no comments available yet for this resource)