Author
Geological Survey (U.S.),
2
United States. Congress. House. Committee on Natural Resources
2
United States. Congress. House. Committee on Transportation and Infrastructure
2
Clow, G. D.,
1
Colorado. Department of Local Affairs
1
Huso, Manuela,
1
Ladd, Lew,
1
Som, Nicholas,
1
United States. Congress. House. Committee on International Relations
1
United States. Congress. House. Committee on Resources
1
United States. Congress. House. Committee on Ways and Means
1
Urban, Frank E.,
1