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. 2020 Nov 22;246:118089. doi: 10.1016/j.atmosenv.2020.118089

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© 2020 The Authors. Published by Elsevier Ltd.

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Fig. 3 — Difference between the observed NO₂ concentrations in 2020 and those from the SC counterfactual (based on the years 2014–2019) at all investigated sites. The vertical dotted line represents the point at which the intervention was implemented.