Field, William D. <br/><br/>
The pierid butterflies of the genera Hypsochila Ureta, Phulia Herrich-Schaffer Infraphulia Field, Pierphulia Field and Piercolias Staudinger 

 - Washimgton :  Smithsonian Institution,  1977 
 - 64 p.  : ilus. 
 - Smithsonian contributions to zoology  ; 232 .
 - Smithsonian contributions to zoology  ; 232 .
<br/><br/><label>LCCN: </label>52743 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mariposas.<br/>Pieridae.