Etgen, Garret J., <br/><br/>
Introduction to ordinary differential equations :  with difference equations, numerical methods, and applications / 
Garret J. Etgen, William L. Morris. 
 - New York :  Harper & Row,  c1977. 
 - x, 517 p. ; 
<br/><br/> Includes index. 
<br/><br/><label>ISBN: </label>006041913X 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Differential equations.<br/>Difference equations.
<br/><br/><label>Universal Decimal Class. No.: </label>517.91  / ETG