Situmorang, Elizabeth Caroline, Andriessa Prameswara, Hana Christine Sinthya, Nurita Toruan-Mathius, and Tony Liwang. 2015. “Indigenous Phosphate Solubilizing Bacteria from Peat Soil for an Eco-Friendly Biofertilizer in Oil Palm Plantation”. KnE Energy 1 (1), 65-72. https://doi.org/10.18502/ken.v1i1.324.