Ferreira, Margarida, Paulo Sá Caetano, e Mafalda Patuleia. 2012. Below and above the Surface: Urban Geotourism on the Lisbon Underground Public Transport. Revista Turismo & Desenvolvimento 3 (17/18), 1639-46. https://doi.org/10.34624/rtd.v3i17/18.13283.