Dyfyniad APA

Barlow, P. M. (2002). Concepts for national assessment of water availability and use. US Geological Survey circular 1223.

Dyfyniad Arddull Chicago

Barlow, Paul M. "Concepts for National Assessment of Water Availability and Use." US Geological Survey Circular 1223 2002.

Dyfyniad MLA

Barlow, Paul M. "Concepts for National Assessment of Water Availability and Use." US Geological Survey Circular 1223 2002.

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