Gerhardus, Maly & Gerhardus, Dietfried <br/><br/>
Expressionism : from artistic commitment to the beginning of a new era 

 - Phaidon, Oxford  1979 
 - 112 
<br/><br/><label>ISBN: </label>0-7148-1951-4 
<br/><br/><label>Dewey Class. No.: </label>759.05 Ger/Ger