Simpson, William Kelly. <br/><br/>
Expedition. the bulletin of the university museum of the university of pennsilvania ;   no. 4 

 - Pennsilvania-US :   Univesity of Pennsylvania,   1962. 
 - páginas 37-47 :   ilustraciones blanco y negro 
 - Trimenstral 
 - Vol.4, no 4(1962)  
 - Expedition. the bulletin of the university museum of the university of pennsilvania ;   no. 4 .
 - University of Pennsylvania. .