Não informado. (2004). SA mining: South African mining, coal, gold, and base minerals. Johnnic Publishing.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. SA Mining: South African Mining, Coal, Gold, and Base Minerals. Pinegowrie, Africa do Sul: Johnnic Publishing, 2004.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. SA Mining: South African Mining, Coal, Gold, and Base Minerals. Johnnic Publishing, 2004.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.