Murray-Rust, D Hammond creator Snellen, W Bart text xx Colombo International Irrigation Management Institute 1993 9999 monographic und xx, 148p.:ills+tab D Hammond Murray-Rust 92-9090-192-6 Irrigation; Irrigation farming; Irrgation Scheduling; Agriculture; Irrigation efficiency; Irrigation-Management 631.7 M983I NITIL 190327