Kawohl, B <br/><br/>
Rearrangements & convexity of level sets in partial differential equations 
B. Kawohl 
 - Berlin  Springer  1985 
 - 136 
 - Lecture notes in mathematics 1150 .
<br/><br/><label>ISBN: </label>3540156933 
<br/><br/><label>Dewey Class. No.: </label>10.02+22  / Kawo