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. 2020 Oct 16;34:100719. doi: 10.1016/j.uclim.2020.100719

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Fig. 6 — The box plots of NO₂ concentration in 12 cities for March, April and May of 2019 and 2020 (left) and percentage change in NO₂ concentration in March, April and May of 2020 as compared to 2019 (right).