books.google.com - Previously published separately, the two books aha! Gotcha and aha! Insight are here combined as a single volume. The aha! books, as they are referred to by fans of Martin Gardner, contain 144 wonderful puzzles from the reigning king of recreational mathematics. In this combined volume, you will find...http://books.google.com/books/about/Aha_A_Two_Volume_Collection.html?id=EV2y4z95_KQC&utm_source=gb-gplus-shareAha! A Two Volume Collection
