Hutapea, P., J. Ginting, and N. Rahmawati. “Growth And Production Of Several Rice Varieties With The Biochar From Different Sources Of Materials”. AGRITEPA: Jurnal Ilmu Dan Teknologi Pertanian, Vol. 9, no. 1, July 2022, pp. 247-58, doi:10.37676/agritepa.v9i1.2026.