W R Walker. (1989). FAO irrgation and drainage paper N.45: Guidelines for designing and evaluating surface irrigation systems. Rome: FAO.
Citação norma ChicagoW R Walker. FAO Irrgation and Drainage Paper N.45: Guidelines for Designing and Evaluating Surface Irrigation Systems. Rome: FAO, 1989.
Citação norma MLAW R Walker. FAO Irrgation and Drainage Paper N.45: Guidelines for Designing and Evaluating Surface Irrigation Systems. Rome: FAO, 1989.
Nota: a formatação da citação pode não corresponder 100% ao definido pela respectiva norma.