1. Genetic stratigraphy of the Waterberg coalfield;Beukes,1991
2. The northern Natal coalfield;Blignaut,1940
3. Die eienskappe van die Waterbergsteenkool met spesiale verwysing na stratigrafiese korrelasie;Botha,1984
4. South African coal resources explained and analysed;Bredell;Geol. Surv. S. Afr., Report 1987 - 0154,1987
5. Managing the interface between coal and the environment in the Republic of South Africa;Bredell,1991