Hexem, R. W., & Heady, E. O. (1978). Water production functions for irrigated agriculture. Iowa State University Press.
Chicago-viite (17. p.)Hexem, Roger W., ja Earl Orel Heady. Water Production Functions for Irrigated Agriculture. Ames: Iowa State University Press, 1978.
MLA-viite (9. p.)Hexem, Roger W., ja Earl Orel Heady. Water Production Functions for Irrigated Agriculture. Iowa State University Press, 1978.
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