ZALKUWI, J.; YUSUF, C.; IBRAHIM, A. Analysis of Cost and Return in Cowpea Production : A Case Study Guyuk Local Government Area of Adamawa State, Nigeria. The International Journal of Humanities & Social Studies, [S. l.], v. 2, n. 12, 2014. Disponível em: https://internationaljournalcorner.com/index.php/theijhss/article/view/140788. Acesso em: 4 jul. 2024.