Hexem, R. W., & Heady, E. O. (1978). Water production functions for irrigated agriculture. Iowa State University Press.
Cita Chicago (17th ed.)Hexem, Roger W., i Earl Orel Heady. Water Production Functions for Irrigated Agriculture. Ames: Iowa State University Press, 1978.
Cita MLA (9th ed.)Hexem, Roger W., i Earl Orel Heady. Water Production Functions for Irrigated Agriculture. Iowa State University Press, 1978.
Atenció: Aquestes cites poden no estar 100% correctes.