Excerpt from Contributions to Economic Geology (Short Papers and Preliminary Reports), 1912, Vol. 2: Mineral Fuels This volume is the seventh of a series that i
Excerpt from Contributions to Economic Geology (Short Papers and Preliminary Reports) 1912, Vol. 1: Metals and Nonmetals Except Fuels This volume is the elevent
Excerpt from Contributions to Economic Geology, Vol. 2: Short Papers and Preliminary Reports, 1915; Mineral Fuels This volume is the ninth of a series that incl