Ojimgba , Onwuchekwa. “Influence of Inorganic Fertilizer (NPK 15:15:15) and Cacao (Theobroma Cacao L) Leaf Litter Application Rates on Cowpea (Vigna Unguiculata L.) Performance in the Tropics”. American International Journal of Agricultural Studies 3, no. 1 (June 20, 2020): 14–32. Accessed June 25, 2024. https://www.acseusa.org/journal/index.php/aijas/article/view/14.