Pardee, J T. <br/><br/>
United States Geological Survey Bulletin ;   no.660-F 

 - Washington-US :   United States Geological Survey Bulletin,   1918. 
 - páginas 159-239 :   IIustraciones blanco y negro 
 - No. 660-F (1918) 
 - United States Geological Survey Bulletin ;   no.660-F .
 - United States Geological Survey. .