Avery, Donald; Schmidt, Peter (1978). "Complex Iron Smelting and Prehistoric Culture in Tanzania". Science. 201 (4361): 1085–1089. ISSN0036-8075. JSTOR1746308.
Avery, Donald; Schmidt, Peter (1978). "Complex Iron Smelting and Prehistoric Culture in Tanzania". Science. 201 (4361): 1085–1089. ISSN0036-8075. JSTOR1746308.