@BOOK {CLAASSEN:1995, title = {Management of tillage equipment on research farms: IITA research guide, No. 10}, author = {Claassen, S. L. }, series = {IITA research guide, No. 10}, year = {1995}, month = {September}, publisher = {International Institute of Tropical Agriculture (IITA)}, address = {Ibadan, Nigeria}, note = {33p.}, }