Studies of the physico-chemical properties of humic simple superphosphate obtained on the basis of Central Kyzylkum phosphorites and oxidized coalPirnazar Ganiev, Shafoat Namazov, Najimuddin Usanbaev, Uktam Temirov and Bakhtiyor NumonovE3S Web Conf., 377 (2023) 03013DOI: https://doi.org/10.1051/e3sconf/202337703013