SPIEGEL ,M.R. Theory and problems of calculus of finite differences and difference equations Murray R.Spiegel - New York Mcgraw-Hill 1971 - 259p. - Schaum's Outline Theory . Including 420 solved problem ISBN: 070602182 USD 5.95 Subjects--Topical Terms: DIFFERENTIAL EQUATIONS, Dewey Class. No.: MATH 515.35&.62076 / SMn71