Não informado. (2003). South African mining, coal, gold & base minerals. Thomson Publication.
Chicago-referens (17:e uppl.)Não informado. South African Mining, Coal, Gold & Base Minerals. Johannesburg, Africa do Sul: Thomson Publication, 2003.
MLA-referens (8:e uppl.)Não informado. South African Mining, Coal, Gold & Base Minerals. Thomson Publication, 2003.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.