APA (7th ed.) Citation

Smith, A. B., & Bengtson, P. (1991). Cretaceous echinoids from north-eastern Brazil. Univ.-Forl.

Chicago Style (17th ed.) Citation

Smith, Andrew B., and Peter Bengtson. Cretaceous Echinoids from North-eastern Brazil. Oslo: Univ.-Forl, 1991.

MLA (9th ed.) Citation

Smith, Andrew B., and Peter Bengtson. Cretaceous Echinoids from North-eastern Brazil. Univ.-Forl, 1991.