Transport externalities of bus stations produced by Greenhouse Gas (GHG) M Córdova-Suárez, E Barreno-Ávila, P Villacrés-Cevallos and O Ruíz-Robalino E3S Web Conf., 167 (2020) 04001 Published online: 24 April 2020 DOI: 10.1051/e3sconf/202016704001