Vermillion, Douglas L.; Sagardoy, Juan A.
(International Water Management Institute (IWMI), Colombo, Sri Lanka, Deutsche Gesellschaft Fur Technische Zusammenarbeig (GTZ), Eschborn, Germany, Food and Agriculture Organization (FAO), Rome, Italy. (FAO Irrigation and Drainage Paper, no. 58)International Water Management Institute (IWMI), Colombo, Sri Lanka, Deutsche Gesellschaft Fur Technische Zusammenarbeig (GTZ), Eschborn, Germany, Food and Agriculture Organization (FAO), Rome, Italy, 1999)