1. Aeromagnetic map of the Butte 1° x 2° quadrangle, Montana [cartographic material] Yale Public content 1984. 2023-08-28T19:44:53Z. 2023-08-29T03:02:39Z. Geological Survey (U.S.). U.S. Geological Survey ; [Books and Open-File Report Section, distributor]. English. cartographic image. Public. Montana and Butte Region.