General geology of the Hahns Peak and Farwell Mountain quadrangles, Routt County, Colorado / by Kenneth Segerstrom and E. J. Young ; with a discussion of Upper Triassic and Pre-Morrison Jurassic rocks by G.N. Pipiringos.
[Washington, D.C.] : United States Department of the Interior, Geological Survey, 1972.
Washington : United States Government Printing Office