APA (7th ed.) Citation

Geological Survey (U.S.) & Geological Survey (U.S.). (1975). Index to maps showing flood-prone areas in North Carolina. Geological Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.) and Geological Survey (U.S.). Index to Maps Showing Flood-prone Areas in North Carolina. Raleigh, Nc.: Geological Survey, 1975.

MLA (9th ed.) Citation

Geological Survey (U.S.) and Geological Survey (U.S.). Index to Maps Showing Flood-prone Areas in North Carolina. Geological Survey, 1975.