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Conservation of natural resources
Smith, Guy-Harold, (1950)
Annual report / USG Corporation
(1984)
Mineral commodity summaries
(1978)
The Eureka Mining District, Nevada
Nolan, Thomas Brennan, (1962)
Supply and demand for United States coking coals and metallurgical coke
Sheridan, Eugene Thomas, (1976)
International Tin Agreement 1953
Harris, Florence E., (1954)