Não informado. (1956). Journal of the Southern African Institute of Mining and Metallurgy. South African Institute of Mining and Metallurgy.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Não informado. Journal of the Southern African Institute of Mining and Metallurgy. Johannesburg, Africa do Sul: South African Institute of Mining and Metallurgy, 1956.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Não informado. Journal of the Southern African Institute of Mining and Metallurgy. South African Institute of Mining and Metallurgy, 1956.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.