Martin, W. T. and Reissner, Eric <br/><br/>
Elementary differential equations / 

 - Massachusetts:  Addison-Wesley,  1964 
 - xiv, 331p. Bibl. Index. 
 - Addison-Wesley series in Mathematics .
<br/><br/><label>ISBN: </label>978-0201045031 
<br/><br/><label>Dewey Class. No.: </label>515.35  / M383.ED