At the present time unusual interest is taken by mining men in the subject of the origin of the deposits of the metallic ores, the extent of the world's supply, and the means of conserving them, for alarming as it may seem the end is already in sight.
Proceedings of the Iowa Academy of Science
©1910 Iowa Academy of Science, Inc.
Keyes, Charles R.
"Theory of Meteoritic Agglomeration and the Ultimate Source of the Ores,"
Proceedings of the Iowa Academy of Science, 17(1), 169-176.
Available at: https://scholarworks.uni.edu/pias/vol17/iss1/23