books.google.com.au - This is a one-of-a-kind reference for anyone with a serious interest in mathematics. Edited by Timothy Gowers, a recipient of the Fields Medal, it presents nearly two hundred entries, written especially for this book by some of the world's leading mathematicians, that introduce basic mathematical tools...http://books.google.com.au/books/about/The_Princeton_Companion_to_Mathematics.html?id=ZOfUsvemJDMC&q=prove&utm_source=gb-gplus-shareThe Princeton Companion to Mathematics