Não informado. (1903). South African Journal of Science. Associated Scientific & Technical Societies of South Africa.
Chicago-viite (17. p.)Não informado. South African Journal of Science. Johannesburg, Africa do Sul: Associated Scientific & Technical Societies of South Africa, 1903.
MLA-viite (8. p.)Não informado. South African Journal of Science. Associated Scientific & Technical Societies of South Africa, 1903.
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