Forsyth, A. R.  <br/><br/>
A tratise on Differential Equations 

 - 6a ed 
 - London :   Macmillan,   1943. 
 - p. 583 
<br/><br/><label>Subjects--Topical Terms: </label><br/>ECUACIONES DIFERENCIALES
<br/><br/><label>Universal Decimal Class. No.: </label>517.91