Linear differential equations and group theory from Riemann to Poincaré / 
by Gray, Jeremy, 
 - 2nd ed. 
 - Boston :  Birkhauser,  2000 
 - xx, 338 p. :  ill.,  24 cm. 
<br/><br/><label>ISBN: </label>0817638377 (alk. paper) | 3764338377 (alk. paper) | 9780817647728 (pbk. :