Bol Gerrit <br/><br/>
Projektive differentialgeometric 

 -  1950 
 - p.  cm. 
<br/><br/><label>Standard No.: </label>24343 
<br/><br/><label>Source: </label> Textual 
<br/><br/><label>Dewey Class. No.: </label>B6:7, 113J0.1;J0.2