The constitution of pinnacle bed coal from Hayden mine, Haybro, Routt county, Colorado,

by May, Timothy Crawford
Washington, D.C., Catholic University of America, 1938

Photographs of historical mining operations in Colorado and Utah from the U.S. Geological Survey Library /

[Reston, Va.?] : [Denver, Colo.] : The Survey ; [For sale by USGS Distribution Branch], 1994