Rohman, A. N., M. F. Barchia, and B. G. Murcitro. “Effect of Biourine on N Uptake and Cabbage (Brassica Oleraceae L) Growth on Lowland Ultisol”. TERRA : Journal of Land Restoration, vol. 3, no. 2, Dec. 2020, pp. 39-44, doi:10.31186/terra.3.2.39-44.