.Suwarno, and Komaruddin Idris. “Potential and Possibility of Direct Use of Guano As Fertilizer in Indonesia”. Jurnal Ilmu Tanah dan Lingkungan 9, no. 1 (April 1, 2007): 37-43. Accessed May 2, 2024. https://journal.ipb.ac.id/index.php/jtanah/article/view/2387.