00314nam a2200097Ia 450000500170000000800410001705000210005810000180007924500930009726000260019020251229183019.0251229s9999    xx            000 0 und d  aRES S 540 .O53T7  aTripp, Robert 4aThe Planning Stage of on farm Research identifying factors for experimentscRobert Tripp  aMexicob CIMMYTc1989