Holt, Michael. Let's play math [electronic resource] / [by] Michael Holt and Zoltan Dienes.. — New York, : Walker, [1973]. — 184 p. : illus. 22 cm. ISBN: 0802704182 9780802704184 LCCN: 72095791 Subjects--Topical Terms: Mathematical recreations. LC Class. No.: QA95 / .H64 1973 Dewey Class. No.: 793.7/4