00428nam a2200169Ia 4500008004100000020001400041041001200055082001000067082001100077100001600088100001100104245008400115260000800199260001500207260000900222650002700231150901s9999    xx            000 0 und d  a821310305  aEnglish  a338.1  bOMA/EF  aOmara G T    eEditor  aEfficiency in irrigation the conjunctive use of surface and goundwater resource  aUSA  bWorld bank  c1989  aAgricultural economics