@BOOK {DVORAK:1995a, title = {Enquetes exploratoires pour la planification de la recherche: Guide de recherche de l'Iita, No. 28}, author = {Dvorak, K. A. and Izac, A. M. N. }, series = {Guide de recherche de l'Iita, No. 28}, year = {1995}, month = {February}, publisher = {International Institute of Tropical Agriculture (IITA)}, address = {Ibadan, Nigeria}, note = {22p.}, }