Nelson, Willis H. (Willis Howard), 1920-
Nelson, Willis H. (Willis Howard), 1920-
Pierce, William Gamewell, 1904-
Contributions to stratigraphy
Wapiti formation and Trout Peak Trachyandesite, northwestern Wyoming,
Wapiti formation and Trout Peak Trachyandesite, northwestern Wyoming,
Wapiti formation and Trout Peak Trachyandesite, northwestern Wyoming,
Nelson, Willis H. (Willis Howard), 1920-