Elen, L. W. F. <br/><br/>
Differential equations, Part 1 / 
L.W.F. Elen. 
 - London :  Macmillan,  c1965. 
 - viii, 220 p. 
<br/><br/> Part 1 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Differential equations.