El Alfy, Youssef 6. Irrigation structures [[Book] /] Youssef El Alfy. - Cairo : October 6 University., 2003. - various pages : ill ; 23 cm. All age. ISBN: 9771932861 Subjects--Topical Terms: Irrigation engineering. Dewey Class. No.: 627.52 National Library of Medicine Call No.: 627.52 / E I