@book{52743,
	author = {Field, William D. and Herrera, José.},
	title = {The pierid butterflies of the genera Hypsochila Ureta, Phulia Herrich-Schaffer Infraphulia Field, Pierphulia Field and Piercolias Staudinger},
	publisher = {Smithsonian Institution,},
	year = {1977},
	series = {Smithsonian contributions to zoology},
	address = {Washimgton :}
}