Não informado. (1961). Forestry in South Africa. Department of Forestry.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Forestry in South Africa. Pretoria, Africa do Sul: Department of Forestry, 1961.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Forestry in South Africa. Department of Forestry, 1961.
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