Kotzé, J.C. “DIE GEOMETRIESE EN RIVIERGRENSE VAN SUIDWES-AFRIKA, MET SPESIALE VERWYSING NA DIE NOORDE EN DIE CAPRIVISTROOK”. Scientia Militaria - South African Journal of Military Studies 18, no. 1 (February 23, 2012). Accessed December 6, 2021. https://scientiamilitaria.journals.ac.za/pub/article/view/412.