00298naa a2200109 a 450000100080000000500110000800800410001910000190006024500440007926000090012377300560013218326542010-01-10       1981    bl ---       0--  u    #d1 aSANCHEZ, P. A.  aAnnual Cropping systems in the tropics.  c1981  tField Crops Researchgv. 4, n. 2, p. 176-177, 1981.