1. Radiometric age measurements on rocks from Southern Africa to the end of 1971;Burger;Dep. Mines, Geol. Surv. S. Afr., Bull.,1973
2. Mode of origin of pyroclastic debris in the Mehoten Formation of the Sierra Nevadas;Curtis;Calif. Univ. Publ. Dep., Dep. Geol. Sci., Bull.,1954
3. Sr-isotope studies on various layered mafic intrusions in Southern Africa;Davies,1970
4. The Usushwama Complex in the southeastern Transvaal, with special reference to its economic potential;Hammerbeck,1977
5. The geology of the country south of Piet Retief;Humphrey,1931