Leppan, H.D. The agricultural development of arid and semi-arid regions with special reference to South Africa / H.D. Leppan - Pretoria : SACNA , 1928 - 280p. : ill. ; 23 cm. Includes bibliographical references and index. Subjects--Topical Terms: AgricultureAgricultural developmentArid regions Dewey Class. No.: 630.96 / LEP