Gurney, J.J., and J.B.M. Hobbs. “Potassium, Thorium and Uranium in Some Kimberlites from South Africa”. International Kimberlite Conference: Extended Abstracts 1 (August 13, 1973): 143–146. Accessed April 24, 2024. https://ikcabstracts.com/index.php/ikc/article/view/869.