Harahap, Fitra Syawal, Abdul Rauf, Benny Hidayat, Hilwa Walida, Jamidi, and Lisdyani. 2018. “Availibility of P, K in Paddy Land Under Organic Application”. Jurnal Online Pertanian Tropik 5 (3):434-40. https://doi.org/10.32734/jopt.v5i3.3117.