Não informado. (1974). Journal of Rural Economics and Development. University of Ibadan, Department of Agricultural Extension Services.
Chicago-viite (17. p.)Não informado. Journal of Rural Economics and Development. Ibadan, Nigeria: University of Ibadan, Department of Agricultural Extension Services, 1974.
MLA-viite (8. p.)Não informado. Journal of Rural Economics and Development. University of Ibadan, Department of Agricultural Extension Services, 1974.
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