1. Aeromagnetic map of the southwestern part of the Flathead National Forest, Montana [cartographic material] Yale Public content 1980. 2002-06-01T04:00:00Z. 2022-12-20T04:01:25Z. Geological Survey (U.S.). The Survey. English. cartographic image. Public. Montana, Flathead National Forest, and Flathead National Forest (Mont.).