@PROCEEDINGS {HARTMANS:1983, title = {Current and future trends in tillage in the humid and subhumid tropics}, author = {Hartmans, E. H. and ter Kuile, C. H. H. }, year = {1983}, publisher = {International Institute of Tropical Agriculture (IITA)}, address = {Ibadan, Nigeria}, note = {Conference paper 1, presented at fifth session of the Food and Agriculture Organization (FAO) Panel of Experts on Agricultural Mechanization, Rome, Italy 20-22 April 1983}, }