Agbede, T. M., and A. O. Adekiya. “Effects of Poultry Manure on Soil Fertility, Growth and Yield of White Yam and Yellow Yam”. University of Khartoum Journal of Agricultural Sciences 20, no. 3 (March 28, 2023). Accessed April 4, 2025. http://onlinejournals.uofk.edu/index.php/uofkjas/article/view/1858.