Geology and ore deposits of the Eureka and adjoining districts, San Juan Mountains, Colorado a study of part of the western San Juan Mountains eruptive center, its related cauldron subsidence structures, altered volcanic rocks, and ore deposits - Burbank, Wilbur S.; Luedke, Robert G. (U.S. Government Print. Office, 1969)
Literaturverz. S. 68 - 70