Gideon, I.K., A.N. Ogbonna, and E.C. Nzegbule. “Soil Physico-Chemical Properties in Three Land Use Systems (Theobroma Cacao, Gmelina Arborea and Secondary Forest) in Umuahia North of Abia State, Nigeria”. Canadian Journal of Agriculture and Crops 1, no. 1 (June 15, 2016): 19–29. Accessed July 3, 2024. https://onlinesciencepublishing.com/index.php/cjac/article/view/366.