Karolev, V. e Olson, R.O. 2017. The myth, reality and future of tourists’ and travel industry responsibilities: a model for sustainable tourism in protected areas and its applications in Bulgaria. Revista Turismo & Desenvolvimento. 2, 27/28 (Jan. 2017), 161-163. DOI:https://doi.org/10.34624/rtd.v2i27/28.8273.