Nunes, João Carlos (2014). "The Azores Archipelago: Islands of Geodiversity". In Erfurt-Cooper, Patricia (ed.). Volcanic Tourist Destinations(PDF). Springer. p. 57. ISBN978-3-642-16190-2. Archived from the original on 14 January 2024. Retrieved 14 January 2024.
Nunes, João Carlos (2014). "The Azores Archipelago: Islands of Geodiversity". In Erfurt-Cooper, Patricia (ed.). Volcanic Tourist Destinations(PDF). Springer. p. 57. ISBN978-3-642-16190-2. Archived from the original on 14 January 2024. Retrieved 14 January 2024.