1. Global Geotourism—An Emerging Form of Sustainable Tourism;Dowling;Czech J. Tour.,2014
2. Theodosiou, E., Fermeli, G., and Koutsouveli, A. (2006). Our Geological Heritage, Kalidoskopio Publications.
3. Geotop. Grundzüge einer Begriffsentwicklung und Definition;Materialien,1993
4. Geotope, Geosite, Geomorphosite;Ielenicz;Ann. Valahia Univ. Târgovişt. Geogr. Ser.,2009
5. Geomorphosites: Definition, assessment and mapping;Reynard;Geomorphol. Reli. Process. Environ.,2005