p40sAr/p39sAr and K-Ar geochronology and tectonic significance of the Upper Cretaceous Adel Mountain volcanics and spatially associated Tertiary igneous rocks, northwestern Montana [electronic resource] / by Stephen S. Harlan ... [et al.].
Imprint
Reston, Va. : U.S. Dept. of the Interior, U.S. Geological Survey, 2005.