Klinger, H. C. (1989). Cretaceous faunas from Zululand and Natal, South Africa: The Ammonite family Placenticeratidae Hyatt, 1900 ; with comments on the systematic position of the genus Hypengonoceras Spath, 1924. South African Museum.
Chicago-Zitierstil (17. Ausg.)Klinger, Herbert Christian. Cretaceous Faunas from Zululand and Natal, South Africa: The Ammonite Family Placenticeratidae Hyatt, 1900 ; with Comments on the Systematic Position of the Genus Hypengonoceras Spath, 1924. Cape Town: South African Museum, 1989.
MLA-Zitierstil (9. Ausg.)Klinger, Herbert Christian. Cretaceous Faunas from Zululand and Natal, South Africa: The Ammonite Family Placenticeratidae Hyatt, 1900 ; with Comments on the Systematic Position of the Genus Hypengonoceras Spath, 1924. South African Museum, 1989.