Zainal, S., Zamre, N.M. and Khan, M.F. 2021. Emission level of air pollutants during 2019 pre-haze, haze, and post-haze episodes in Kuala Lumpur and Putrajaya. Malaysian Journal of Chemical Engineering & Technology. 4, 2 (Oct. 2021), 137–154. DOI:https://doi.org/10.24191/mjcet.v4i2.14299.