Differential equation : A systems approach 
Goldberg, Jack. 
 -  Prentice Hall, Inc.  1998 
 - 496 pages. 
<br/><br/>
<br/><br/><label>ISBN: </label>0-13-752080-8 
<br/><br/><label>Dewey Class. No.: </label>515.35 G56d 1998