Note 41 — Chapter XIV · EXPLORATION AND DEVELOPMENT
Reading edition
Van Hise, C. R., and Leith, C. K., Geology of the Lake Superior region: Mon. 52, U.S. Geol. Survey, 1911.
Reading edition
Van Hise, C. R., and Leith, C. K., Geology of the Lake Superior region: Mon. 52, U.S. Geol. Survey, 1911.