A model of introducing Clean Transport Zones in Poland – between optionality and obligatoriness. Discourse of Law and Administration, [S. l.], n. 2, p. 61–72, 2023. DOI: 10.34768/dpia.2022.2.252. Disponível em: https://www.dyskurs.inp.uz.zgora.pl/index.php/DPiA/article/view/252. Acesso em: 5 dec. 2025.