1. S. Ritung, E. Suryani, D. Subardja, Sukarman, K. Nugroho, Suparto, Hikmatullah, A. Mulyani, C. Tafakresnanto, Y. Sulaeman, R. E. Subandiono, Wahyunto, Ponidi, N. Prasojo, U. Suryana, H. Hidayat, A. Priyono and W. Supriatna, “Sumberdaya Lahan Pertanian Indonesia: Luas, Penyebaran, dan Potensi Ketersediaan,” edited by E. Husen, F. Agus, dan D. Nursyamsi (IAARD Press, Jakarta, 2015), p. 98.
2. S. Hardjowigeno, Ilmu tanah 7th ed. (Akademika Pressindo, Jakarta, 2010), p. 220.
3. H. Y. Ch’ng, O. H. Ahmed and N. M. A. Majid, The Sci. World J. (2014).
4. R. R. Weil and N. C. Brady, The Nature and properties of soils 15th ed. (Persson Education Limited, England, 2017), p. 1.105.
5. Release of Inorganic Phosphorus from Soils by Low‐Molecular‐Weight Organic Acids