@BOOKLET {HARTMANS:1981, title = {Land development and management in tropical Africa}, author = {Hartmans, E. H. }, year = {1981}, address = {Ibadan, Nigeria}, howpublished = {In: Paper Presented at the Sixth Session of FAO Committee on Agriculture, Rome 25 March - 3 April 1981}, note = {Paper Presented at the Sixth Session of FAO Committee on Agriculture, Rome 25 March - 3 April 1981.; 22p.}, }