books.google.co.uk - These clearly and cleverly presented mathematical recreations of paradoxes and paperfolding, Moebius variations and mnemonics both ancient and modern delight and perplex while demonstating principles of logic, probability, geometry, and other mathematical fields."A classic."—Andrew Rothery, Times Education...http://books.google.co.uk/books/about/Hexaflexagons_and_Other_Mathematical_Div.html?id=QpPlxwSa8akC&utm_source=gb-gplus-shareHexaflexagons and Other Mathematical Diversions
