Kumolontang, Wiesje J.N., et al. “Testing of the N, P, and K Nutrients in Rice Soil in the Kalawarat District of North Minahasa Regency”. Jurnal Agroekoteknologi Terapan (JAT), vol. 5, no. 1, Feb. 2024, pp. 75-81, doi:10.35791/jat.v5i1.54506.