References:
- Wilson, W.E. & Dunn, P.J.(1978): Famous localities: The Kalahari manganes field. Mineralogical Record 9: 137-153
- Cairncross, B., Beukes, N. and Gutzmer, J. (1997): The manganese adventure – the South African manganese fields. Associated Ore & Metal Corporation Limited, Johannesburg, Republic of South Africa, 236 pp.