共 50 条
- [37] Bulkheads for coal mines TRANSACTIONS OF THE AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS, 1938, 130 : 284 - 301
- [38] Demonstration coal mines TRANSACTIONS OF THE AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS, 1920, 63 : 945 - 948
- [39] THE COAL MINES OF PENNSYLVANIA ANNALS OF THE AMERICAN ACADEMY OF POLITICAL AND SOCIAL SCIENCE, 1911, 38 : 133 - 138