Falodun, E., A. Osaigbovo, and S. Remison. “Effect of Palm Oil Mill Effluent and NPK 15:15:15 Fertilizer on the Growth and Yield of Soya Bean”. Bayero Journal of Pure and Applied Sciences, vol. 4, no. 2, Apr. 2012, pp. 173-7, doi:10.4314/bajopas.v4i2.35.