United States Department of the Interior
From the introduction: The Bureau of Mines has been investigating deposits of critical and essential minerals in the United Sates and Alaska since 1939. During the fall of 1942, the Bureau of Mines put down nine diamond-drill holes at the Cape Rosier zinc-copper-lead mine in Hancock County, Maine, that aggregated 2,883 feet of bore... This report describes the work done by the Bureau of Mines and presents the data obtained in the two periods of drilling.
Report of Investigations no. 4344 (R. I. 4344).
Levin, S. B. and Sanford, Robert S., "Investigation of the Cape Rosier Zinc-Copper-Lead Mine, Hancock County, Maine" (1948). Maine History Documents. 293.
publisher's version of the published document