APA aipamena

Cobban, W., & Kennedy, W. (1991). Some Upper Cretaceous ammonites from the Nacatoch Sand of Hempstead County, Arkansas.

Chicago Style aipamena

Cobban, W., and W. Kennedy. Some Upper Cretaceous Ammonites from the Nacatoch Sand of Hempstead County, Arkansas. 1991.

MLA aipamena

Cobban, W., and W. Kennedy. Some Upper Cretaceous Ammonites from the Nacatoch Sand of Hempstead County, Arkansas. 1991.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.