Byambasuren, T., B. Khuukhenkhuu, G. Ochirbat, and D. Tsedenbaljir. “Temporal Variation of the Pseudo Total Content of Heavy Metals in Ulaanbaatar Soil”. Proceedings of the Mongolian Academy of Sciences, vol. 59, no. 3, Dec. 2019, pp. 21-28, doi:10.5564/pmas.v59i3.1243.