Balzan, M.V. and Debono, I., 2018. Assessing urban recreation ecosystem services through the use of geocache visitation and preference data: a case-study from an urbanized island environment. One Ecosystem, v. 3, e24490.
Birch, J. et al, 2014. What benefits do community forests provide, and to whom? A rapid assessment of ecosystem services from a Himalayan Forest Nepal. Ecosystem Services, v. 8, p. 118‑127.
Brandolini, P. et al, 1994. Recherché ambientali per l’individuazione e la valutazione dei Beni geomorfologici – metodi ed esempi. II Quaternario, v. 7(1), p. 365-372.
Comanescu, L., Nedelea, A. and Dobre, R., 2011. Evaluation of geomorpho-sites in Vistea Valley (Fagaras Mountains-Carpathians, Romania). International Journal of the Physical Sciences, v. 6, p. 1161-1168.
Comanescu, L., Nedelea, A. and Dobre, R., 2012. The evaluation of geomorphosites from Ponoare protected area. Forum geografic. Studii și cercetări de geografie și protecția mediului, v. XI(1), p. 54-61.
Comanescu, L., Nedelea, A. and Stanoiu, G., 2017. Geomorphosites and geotourism in Bucharest City center (Romania). Quaestiones Geographicae, v. 36(3), p. 51-61.
Coratza, P. and Giusti, C., 2005. Methodological proposal for the assessment of the scientific quality of geomorphosites. IL Quaternario, Italian Journal of Quaternary Science, v. 18(1), p. 305-313.
Darfashi, K., 2023. Quantitative evaluation of natural heritage sites of southern coasts of the country, a new approach in development planning for nature-based tourism destination. Research project report (unpublished). Natural Heritage Department, Cultural Heritage and Tourism Research Institute, 185 p (In Persian).
Darfashi, K. and Seyed Hamzeh, M., 2021. Natural heritage potential zoning in Sistan and Baluchistan Province based on Geographical Information System (GIS) and FAHP model. Research project report (unpublished). Natural Heritage Department, Cultural Heritage and Tourism Research Institute, 193 p (In Persian).
Derafshi, K. and Seyyed Hamzeh, M., 2022. Synthesis of quantitative geosite assessment models and its application on Sistan and Baluchestan Province natural heritages, potential geotourism destination of Iran. Geoheritage, v. 14(124), p. 1-28 (In Persian).
Drumm, A. and Moore, A., 2005. Ecotourism development – A manual for conservation planners and managers: Volume I – an introduction to ecotourism planning. Arlington, VI: The Nature Conservancy.
Esna Ashari, A. and Saed Mucheshi, A., 2019. Geoheritage: definition, classification, qualitative and quantitative assessment, its relation with the tourism, Examples from Iran. New Findings in Applied Geology, v. 13(26), p. 141-155 (In Persian).
Fassoulas, C., Mouriki, D., Dimitriou-Nikolakis, P. and Iliopouslos, G., 2012. Quantitative assessment of geotopes as an effective tool for geoheritage management. Geoheritage, v. 4(3), p. 177-193.
Fotouhi, S., Taghizadeh, Z. and Rahimi, D., 2012. Evaluation of geomorpho-tourism capabilities of landforms based on Pralong method, Case study; Bisetoon Tourism Sample Area. Applied Researches in Geographical Sciences, v. 12(26), p. 23-46 (In Persian).
Garnache, C., Srivastava, L., Sánchez, J., and Lupi, F., 2018. Recreation ecosystem services from chaparral dominated landscapes: A baseline assessment from national forests in southern California. Springer Series on Environmental Management, p. 271‑294.
Gordon, J.E., Bailey, J. and Larwood, J., 2022. Conserving nature's stage provides a foundation for safeguarding both geodiversity and biodiversity in protected and conserved areas. Parks Stewardship Forum, v. 38(1), p. 46-56.
Gordon, J.E., Crofts, R., Gray, M. and Tormey, D., 2021. Including geoconservation in the management of protected and conserved areas matters for all of nature and people. International Journal of Geoheritage and Parks, v. 9(3), p. 323-334.
Harrison, R. and O'Donnel, D., 2010. Natural heritage. In: West S (Ed.) Understanding heritage in practice. 1st edition, Manchester University Press, Manchester, 328 p.
Hose, T.A., 2012. 3G’s for modern geotourism. Geoheritage, v. 4(1-2), p. 7-24.
Ihtimanski, I., Nedkov, S. and Semerdzhieva, L., 2020. Mapping the natural heritage as a source of recreation services at national scale in Bulgaria. One Ecosystem, v. 5, e54621.
Jennings, S., 2004. Coastal tourism and shoreline management. Annals of Tourism Research, v. 31(4), p. 23-34.
Kabiri-e Hendi, M. and Danehkar, A., 2011. An integrated approach to the management and conservation of natural and cultural heritage. Archaeological Letter, v. 1(1), p. 147-159 (In Persian).
Kienast, F., Degenhardt, B., Weilenmann, B., Wäger, Y. and Buchecker, M., 2012. GIS-assisted mapping of landscape suitability for nearby recreation. Landscape and Urban Planning, v. 105(4), p. 385‑399.
Koniak, G., Sheffer, E. and Noy-Meir, I., 2011. Recreation as an ecosystem service in open landscapes in the Mediterranean region in Israel: Public preferences. Israel Journal of Ecology and Evolution, v. 57, p. 151‑171.
Kornienko, S.I., Kruglova, A.S. and Pyankov, S.V., 2015. Historical and cultural heritage of Perm region: conservation, visualization and study of GIS-technologies. Sustainable Development of Territories: cartography and GIS software. Conference Papers, Krasnodar: KGU, p. 124-132.
Kubalíková, L., 2013. Geomorphosite assessment for geotourism purposes. Czech Journal of Tourism, v. 2(2), p. 80-104.
Kubalíková, L. and Kirchner, K., 2016. Geosite and geomorphosite assessment as a tool for geoconservation and geotourism purposes: a case study from Vizovická Vrchovina highland (eastern part of the Czech Republic). Geoheritage, v. 8, p. 5-14.
Kubalíková, L. and Kirchner, K., 2013. Relief assessment methodology with respect to geoheritage based on example of the Deblinska vrchovina highland. In: Fialová J, Kubíčková H (eds) Public recreation and landscape protection - with man hand in hand. Mendel University in Brno, p. 131-141.
Kubalíková, L., Krichner, K., Kuda, F. and Bajer, A., 2020. Assessment of Urban Geotourism Resources: An Example of Two Geocultural Sites in Brno, Czech Republic. Geoheritage, v. 12(7), p. 1-12.
Leopold, A., 1949. A Sand County Almanac. Oxford University, Press, 280 p.
Maghsoudi, M., Ganjaeian, H., Fereidouni Kordestani, M. and Ebrahimi, A., 2018. Prone areas the development of geosites based on assessment zoning and methods (Case study: Marivan Township). Territory, v. 15(57), p. 49-68 (In Persian).
Maghsoudi, M., Ganjaeian, H., Garosi, L. and Moradi, A., 2018. Evaluating and zoning East Kurdistan Geosites- Case Study: Qorveh and Bijar Counties. Scientific- Research Quaterly of Geographical Data (SEPEHR), v. 27(107), p. 133-148 (In Persian).
Mallarach, J.M. and Verschuuren, B., 2019. Changing concepts and values in natural heritage conservation: A view through IUCN and UNESCO policies. In: Avrami, E., Macdonald, S., Mason, R., Myers, D. (Eds) Values in Heritage Management: Emerging Approaches and Research Directions. The Getty Conservation Institute, Los Angeles, CA, USA. URL.
Martini, G., Alcala, L., Brilha, J.B., Lantria, L., Sa, L. and Tourtellot, J., 2012. Reflections about the geotourism concept. In: Sá AA, Rocha D, Paz A, Correia V (eds) Proceedings of the 11 European Geoparks Conference. AGA - Associação Geoparque Arouca, Arouca, p. 187-188.
Mouriki, D. and Fassoulas, C., 2009. Quantitative assessment of Psiloritis’ geotopes with emphasis on protection and geotourism (Crete, Greece). In: Neto de Carvalho, C., and Rodrigues, J. (eds). New challenges with geotourism. 8th European Geoparks Congress, Idanha Nova. Portugal, v. 5, p. 199-200.
Mucivuna, V.C., Reynard, E. and Motta Garcia, M.dG., 2019. Geomorphosites assessment methods: comparative analysis and typology. Geoheritage, v. 11(4), p. 1799-1815.
Nahuelhual, L., Carmona, A., Lozada, P., Jaramillo, A. and Aguayo, M., 2013. Mapping recreation and ecotourism as a cultural ecosystem service: An application at the local level in Southern Chile. Applied Geography, v. 40, p. 71‑82.
Nedkov, S., Borisova, B., Nikolova, M., Zhiyanski, M., Dimitrov, S., Mitova, R., Koulov, B., Hristova, D., Prodanova, H., Semerdzhieva, L., Dodev, Y., Ihtimanski, I. and Stoyanova, V., 2021b. A methodological framework for mapping and assessment of ecosystem services provided by the natural heritage in Bulgaria. Journal of the Bulgarian Geographical Society, v. 45, p. 7‑18.
Nedkov, S., Mitova, R., Nikolova, M., Borisova, B., Hristova, D., Semerdzhieva, L., Zhiyanski, M. and Prodanova, H., 2021a. Prioritization of ecosystem services related to the natural heritage of Bulgaria. Journal of the Bulgarian Geographical Society, v. 45, p. 19‑30.
Nedkov, S., Nikolova, M., Prodanova, H., Stoychena, V., Hristova, D. and Sarafova, E., 2022. A multi-tiered approach to map and assess the natural heritage potential to provide ecosystem services at a national level. One Ecosystem, v. 7, p. 1-23.
Newsome, D. and Dowling, R.K., 2010. Geotourism: the tourism of geology and landscape. Goodfellow Publishing Limited, 248 p.
Nikolova, M., Nedkov, S., Borisova, B., Zhiyanski, M. and Dimitrov, S., 2021. Natural heritage as a source of ecosystem services for recreation and tourism in Bulgaria. Journal of the Bulgarian Geographical Society, v. 45, p. 3‑6.
Panizza, M., 2001. Geomorphosites: concepts, methods and example of geomorphological survey. Chinese Science Bulletin, v. 46, p. 4-6.
Pereira, P., Pereira, D., Caetano, M. and Braga, A., 2007. Geomorphosite assessment in Montesinho Natural Park (Portugal). Geographica Helvetica, v. 62(3), p. 159-168.
Pralong, J.P., 2005. A method for assessing the tourist potential and use of geomorphological sites. Geomorphologie. Relief, processus, environment, v. 3, p. 189-196.
Prodanova, H., 2021. Experimental mapping and assessment of ecosystem services based on multi-level landscape classification. Journal of the Bulgarian Geographical Society, v. 45, p. 31‑39.
Reynard, E., 2008. Scientific research and tourist promotion of geomorphological heritage. Geografia Fisica E Dinamica Quaternaria, v. 31, p. 225-230.
Reynard, E., Fontana, G., Kozlik, L. and Scapozza, C., 2007. A method for assessing ‘scientific’ and ‘additional values’ of geomorphosites. Geographica Helvetica, v. 62(3), p. 148-158.
Reynard, E., Perret, A., Bussard, J., Grangier, L. and Martin, S., 2016. Integrated approach for the inventory and management of geomorphological heritage at the regional scale. Geoheritage, v. 8(1), p. 43-60.
Safari, A., Ganjaeian, H., Fereidouni Kordestani, M. and Heidari, Z., 2019. Review capabilities geotourism using assessment and zoning methods (Case study: Divandarreh and Saghez Townships). Geographical Planning of Space, v. 9(31), p. 141-155 (In Persian).
Semerdzhieva, L. and Borisova, B., 2021. Urban ecosystems assessment: An integrated approach to maintenance of habitats and their biodiversity. Journal of the Bulgarian Geographical Society, v. 45, p. 99‑106.
Serrano, E. and Gonzalez-Trueba, J.J., 2005. Assessment of geomorphosites in natural protected areas: the Picos de Europa National Park (Spain). Geomorphologie. Formes, processus, environment, v. 3, p. 197-208.
Servati, M.R. and Kazazi, A., 2008. Geotourism and its planning opportunities in Hamedan Province. Geographical Space, v. 16, p. 1-37 (In Persian).
Silvestriev, M., Borisova, B. and Mitova, R., 2021. Natural heritage: Provision of cultural ecosystem services from the Malyovitsa Range of the Rila National Park. Journal of the Bulgarian Geographical Society, v. 45, p. 41‑59.
Sonter. L.J., Watson, K.B., Wood, S.A. and Ricketts, T.H., 2016. Spatial and temporal dynamics and value of nature-based recreation, estimated via social media. PLOS One, v. 11(9), e0162372.
Strba, L., Rybár, P., Baláž, B., Molokáč, M., Hvizdák, L., Kršák, B., Lukáč, M., Muchová, L., Tometzová, D., and Ferenčíková, J., 2015. Geosite assessments: comparison of methods and results. Current Issues in Tourism, v. 18(5), p. 496-510.
Tardieu, L. and Tuffery, L., 2019. From supply to demand factors: What are the determinants of attractiveness for outdoor recreation? Ecological Economics, v. 161, p. 163‑175.
Tomić, N. and Bozik, S., 2014. A modified Geosite Assessment Model (M-GAM) and its application on the Lazar Canyon area (Serbia), International Journal of Environmental Researches, v. 8(4), p. 1041-1052.
Tomić, N., Sepehroannasab, B., Markovic, S.B., Hao, Q. and Lobo, H.A.S., 2021. Exploring the preferences of Iranian geotourists: case study of Shadows Canyon and Canyon of Jinns. Sustainability, v. 13(798), p. 1-18.
UNESCO, 1972. World heritage convention. Standard-setting at UNESCO.
Vallecillo, S., La Notte, A., Ferrini, S. and Maes, J., 2019. How ecosystem services are changing: an accounting application at the EU level. Ecosystem Services, v. 40, 101044.
Vujicic, M., Vasiljevic, D., Markovic, S., Hose, T., Lukic, T., Hadzic, O. and Janievic, S., 2011. Preliminary geosites assessment model (GAM) and its application on Fruska Gora Mountain, potential geotourism detinarion of Serbia. Acta Geographica Slovenica, v. 51(2), p. 361-377.
Willibald, F., Van Strien, M., Blanco, V. and Grêt-Regamey, A., 2019. Predicting outdoor recreation demand on a national scale - The case of Switzerland. Applied Geography, v. 113(3), 102111.
Yuxi, Z., Linsheng, Z. and Ling-en, W., 2018. Spatiotemporal changes in recreation potential of ecosystem services in Sanjiangyuan, China. Journal of Spatial Science, v. 63(2), p. 359‑377.
Zouros, N.C., 2007. Geomorphosite assessment and management in protected areas of Greece Case study of the Lesvos island - coastal geomorphosites. Geographica Helvetica, v. 62(3), p. 169-180.