Leppan, H. D. (1928). The agricultural development of arid and semi-arid regions: With special reference to South Africa. Central News Agency.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रLeppan, Hubert Dudley. The Agricultural Development of Arid and Semi-arid Regions: With Special Reference to South Africa. [Pretoria?] South Africa: Central News Agency, 1928.
एमएलए (8वां संस्करण) प्रशस्ति पत्रLeppan, Hubert Dudley. The Agricultural Development of Arid and Semi-arid Regions: With Special Reference to South Africa. Central News Agency, 1928.
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