| Henwood, W.J. (1871) Observations on Metalliferous Deposits: On the Native Copper of Lake Superior. Transactions of the Royal Geological Society of Cornwall 8(1): 385-489. Mineralogical Record 23(2) Rocks & Minerals 58, 111 Rocks & Minerals 84, 298-323. |
Central Mine, Central, Houghton Township, Keweenaw County, Michigan, USA