@PROCEEDINGS {ASHRAF:1984a, title = {A farming systems approach to the transfer of improved cowpea varieties}, author = {Ashraf, M. }, booktitle = {Presented at the First World Cowpea Research Conference, 4-9 November, IITA}, year = {1984}, publisher = {International Institute of Tropical Agriculture (IITA)}, address = {Ibadan, Nigeria}, }