APA (7th ed.) Citation

Geological Survey (U.S.). (1966). Culebra and adjacent islands, P.R. Geological Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.). Culebra and Adjacent Islands, P.R. Washington, D.C.: Geological Survey, 1966.

MLA (9th ed.) Citation

Geological Survey (U.S.). Culebra and Adjacent Islands, P.R. Geological Survey, 1966.

Warning: These citations may not always be 100% accurate.