Duggan, Stephen P. <br/><br/>
The Ph,D.Degree-its international significance. 

 - New York-US :   The institute of international education,   1931. 
 - páginas 2-3 
 - Irregular 
 - Vol.VI, no.6 (Mar.1931) 
 - News bulletin  ;   no.6 .
 - The institute of international education. .