Não informado. (1960). Technical communication. Department of Agriculture and Water Supply.
Chicago-viite (17. p.)Não informado. Technical Communication. Pretoria, Africa do Sul: Department of Agriculture and Water Supply, 1960.
MLA-viite (8. p.)Não informado. Technical Communication. Department of Agriculture and Water Supply, 1960.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.