CYBULA, Piotr; ZAWISTOWSKA, Hanna. A Discussion about the Need for New Regulations in Tourism. Studia Oeconomica Posnaniensia, Poznan, Polska, v. 5, n. 4, p. 29–49, 2017. DOI: 10.18559/SOEP.2017.4.2. Disponível em: https://journals.ue.poznan.pl/soep/article/view/3534. Acesso em: 3 sep. 2026.