The skeleton key of mathematics; a simple account of complex algebraic theories. Littlewood, Dudley Ernest. Algebra. QA155 .L5 510 LIS London, New York, Hutchinson's University Library, 1949. 1949. 1949 Text 138 p. ; eng Hutchinson's University Library: Mathematical and physical sciences, no. 18 Hutchinson's university library. Mathematical and physical sciences ; no. 18.