Bell, E T <br/><br/>
Remark on the Number of Classes of Binary Quadratic Forms of a Given Negative Determinant.  [electronic resource] 

 -  Proceedings of the National Academy of Sciences of the United States of America  May 1928 
 - 430-1 p.  digital 
<br/><br/> Publication Type: Journal Article 
<br/><br/><label>ISSN: </label>0027-8424 
<br/><br/><label>Standard No.: </label>10.1073/pnas.14.5.430  doi