Boyce, William E. <br/><br/>
Elementary differential equations / 
William E. Boyce, Richard C. DiPrima. 
 - 3rd ed. 
 - New York :  Wiley,  c1977. 
 - various pagings :  ill. 
<br/><br/><label>ISBN: </label>0471093394 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Differential equations.