J. A, Idoko; B. A, Kalu; P. O, Osang. Influence of Maize Varieties and Date of Planting Cowpea into Maize/Cowpea Intercropping System in Makurdi, Southern Guinea Savannah, Nigeria. International Journal of Sciences: Basic and Applied Research (IJSBAR), Jordan, v. 38, n. 1, p. 98–113, 2018. Disponível em: https://www.gssrr.org/JournalOfBasicAndApplied/article/view/8861. Acesso em: 6 dec. 2025.