Plafker, George <br/><br/>
Geologic Investigation of Proposet Power Sites at Cooper, Grant, Ptarmigan and Crescent Lakes Alaska 

 - Washington, D.C :   Government Printing Office,   1955. 
 - iv, 23 p. :   il. ;   18 cm. 
 - United States Depatments of the Interior. Geological survey bulletin ;   1031-a .