Lorenz, V., S. Kurszlaukis, T. Stachel, G. Brey, I.G. Stanistreet, and L. Franz. “Volcanology of the Diatreme-Rich Carbonatitic Gross Brukkaros Volcanic Field and of the Nearby Gibeon Kimberlite Province, Namibia”. International Kimberlite Conference: Extended Abstracts 6, no. 1 (September 19, 1995): 333-335. Accessed December 13, 2019. http://ikcabstracts.com/index.php/ikc/article/view/1883.