Leppan, H. D. (1928). The agricultural development of arid and semi-arid regions: With special reference to South Africa. Central News Agency.
Chicago Style aipamenaLeppan, Hubert Dudley. The Agricultural Development of Arid and Semi-arid Regions: With Special Reference to South Africa. [Pretoria?] South Africa: Central News Agency, 1928.
MLA aipamenaLeppan, Hubert Dudley. The Agricultural Development of Arid and Semi-arid Regions: With Special Reference to South Africa. Central News Agency, 1928.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.