APA

United States, . (1930). Depletion of mines: hearings, 71st Congress, 3d session, Dec. 9-12, 1930 [with index]. [Washington, D.C.]: .

Chicago

United States, . 1930. Depletion of mines: hearings, 71st Congress, 3d session, Dec. 9-12, 1930 [with index]. [Washington, D.C.]: .

Harvard

United States, . (1930). Depletion of mines: hearings, 71st Congress, 3d session, Dec. 9-12, 1930 [with index]. [Washington, D.C.]: .

MLA

United States, . Depletion of mines: hearings, 71st Congress, 3d session, Dec. 9-12, 1930 [with index]. [Washington, D.C.]: . 1930.