Boruvka, Otakar. <br/><br/>
Linear differential transformations of the second order   
by Otakar Boruvka, tr. by F.M.Arscott 
 - London  English Universities Press  1971 
 - xvi, 254p. 
<br/><br/><label>ISBN: </label>0340124083 
<br/><br/><label>Dewey Class. No.: </label>515.352  / N712