Fourth congress on irrigation and drainage = quatrieme congres des irrigations et du drainage 

 - volúmenes 
<br/><br/> A la cabeza de la portada: printed with the financial assistance of unesco 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Riego--Congresos<br/>Drenaje--Congresos
<br/><br/><label>LC Class. No.: </label>TC401  / C64