Não informado. (1964). Bulletin of Rural Economics and Sociology. University of Ibadan, Department of Agricultural Economics and Extension.
Chicago-referens (17:e uppl.)Não informado. Bulletin of Rural Economics and Sociology. Ibadan, Nigeria: University of Ibadan, Department of Agricultural Economics and Extension, 1964.
MLA-referens (8:e uppl.)Não informado. Bulletin of Rural Economics and Sociology. University of Ibadan, Department of Agricultural Economics and Extension, 1964.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.