Dyfyniad APA

Division, U. S. G. S. W. R. A history of the Water Resources Division, US Geological Survey. Washington.

Dyfyniad Arddull Chicago

Division, United States Geological Survey Water Resources. A History of the Water Resources Division, US Geological Survey. Washington.

Dyfyniad MLA

Division, United States Geological Survey Water Resources. A History of the Water Resources Division, US Geological Survey. Washington.

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