Não informado. (2003). South African mining, coal, gold & base minerals. Thomson Publication.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. South African Mining, Coal, Gold & Base Minerals. Johannesburg, Africa do Sul: Thomson Publication, 2003.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. South African Mining, Coal, Gold & Base Minerals. Thomson Publication, 2003.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.