Yazar
Bolsa Mexicana de Valores
2
Maden Tetkik ve Arama Enstitüsü (Turkey)
2
Austria. Oberste Bergbehörde
1
India. Department of Mines
1
India. Dept. of Mines
1
India. Directorate-General of Mines Safety
1
Neale, Walter Garfield
1
Plate, Horatio Robinson, 1877-
1
Rand, Lenox Hawes
1
Skinner, Edmond Norton
1
Sturgis, Edward Barney, 1873-
1
Weed, Walter Harvey, 1862-1944
1