Non-uniformity in outdoor CO2 concentration in city of CopenhagenHiroki Takahashi, Mariya Petrova Bivolarova, Athanasia Keli, Jürgen Nickel and Arsen Krikor MelikovE3S Web Conf., 111 (2019) 02007DOI: https://doi.org/10.1051/e3sconf/201911102007