SUJIMAN, Sujiman. “Trends in Ambient Air Quality (NO2 and SO2) in Tenggarong City, Kutai Kartanegara District. East Kalimantan”. International Journal of Environmental, Sustainability, and Social Science, vol. 4, no. 5, Sept. 2023, pp. 1497-04, doi:10.38142/ijesss.v4i5.854.