00399nam a2200121Ia 4500008004100000082003400041100003100075245005700106260005100163300001500214600001400229650003400243140117s9999    xx            000 0 und d  a"016:631.58(100) ""1977"" L9"  a"Ramos, Mila Medina comp."  aInternational bibliography on cropping systems 1977.  b"Library and Documentation Centre, IRRI"c1979  a"xv,239p."  aLos Banos  aCropping systems-Bibliography