Azzaya, T., S. Toyoda, N. Yoshida, H. Shiomi, and R. Kouno. “Source Identification of N2O Produced During Simulated Wastewater Treatment under Different Oxygen Conditions Using Stable Isotopic Analysis”. Mongolian Journal of Chemistry, vol. 15, Dec. 2014, pp. 4-10, doi:10.5564/mjc.v15i0.313.