@book{ 0-1113962550, title = {Ages of selected intrusive rocks and associated ore deposits in the Colorado Mineral Belt: sixty-three fission-track and K-Ar age determinations help understand the temporal and spatial evolution of the Colorado Mineral Belt}, series = {US Geological Survey bulletin}, author = {Cunningham, Charles G.}, address = {Washington, DC}, publisher = {United States Gov. Print. Office}, year = {1994}, language = {English}, url = {https://katalog.ub.tu-freiberg.de/Record/0-1113962550} }