Não informado. (1982). National Water Conditions. U.S. Department of the Interior, Geological Survey.
Chicago-viite (17. p.)Não informado. National Water Conditions. Reston, Va: U.S. Department of the Interior, Geological Survey, 1982.
MLA-viite (8. p.)Não informado. National Water Conditions. U.S. Department of the Interior, Geological Survey, 1982.
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