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Potomac River - Wikipedia
Potomac, Maryland - Wikipedia
Potomac River | Maryland, Virginia, Washington DC, & Map
A Guide to the Potomac River - Washingtonian
Potomac River - American Rivers
Potomac River - WorldAtlas
Potomac Basin Facts - ICPRB
RiverExplorer - Potomac River Guide
Potomac Conservancy
101 River Facts — Potomac Conservancy