His Introduction to the theory of finite groups, 1949.
Independent online ed., June 1, 2009 (Professor Walter Ledermann; b. Mar. 18, 1911, Berlin; d. May 22, 2009, London; highly respected mathematician with an eclectic range of interests)
Information from 678 converted Dec. 17, 2014 (Ph.D., D.Sc.)
Introduction to the theory of finite groups , 1967: title page (Walter Ledermann ; Professor of Mathematics in the University of Sussex)