Ross, Shepley L. Introduction to ordinary differential equations / Shepley L. Ross, with the assistance of Shepley L. Ross, II. - 3rd ed. - New York : Wiley, c1980 - xi, 503 p. : ill. ; 24 cm. Includes index. Bibliography: p. [558]. Subjects--Topical Terms: Differential equations. Dewey Class. No.: 515.352 / ROI 1980