Arifin, M. ., P. . Sukaryorini, and T. . Mujoko. “Efficiency of Using NPK Fertilizer With Vermicompost Addition to Growth and Results of Soybean Plants”. Nusantara Science and Technology Proceedings, Apr. 2019, pp. 1-10, https://nstproceeding.com/index.php/nuscientech/article/view/76.