Shpynova, N.V., Sartakov, M.P., Komissarov, I.D. and Grekhova, I.V. 2018. Comparative characteristics of thermal stability of humic acids of sapropels of the middle ob region and south of OB-Irtysh Basin of Wstern Siberia. Amazonia Investiga. 7, 17 (Dec. 2018), 79–84.