APA aipamena

Survey, U. S. G. US Geological Survey circular. Washington, DC [u.a.].

Chicago Style aipamena

Survey, United States Geological. US Geological Survey Circular. Washington, DC [u.a.].

MLA aipamena

Survey, United States Geological. US Geological Survey Circular. Washington, DC [u.a.].

Kontuz: berrikusi erreferentzia hauek erabili aurretik.