Partners
- Bulgarian Academy of Sciences ((2012, 2015, 2019)
- Directorate of Nature Park “Shumen Plateau”, Shumen, Bulgaria (2005)
- Foundation Center of Karstology "Vladimir Popov" (2005, 2012, 2015, 2019)
- Bulgarian Ministry of Education and Science (2012, 2019)
- National Museum "Earth and Man", Sofia, Bulgaria (2005)
- Regional public Library "Stilian Chilingirov” in Shumen, Bulgaria (2005, 2012)
- Municipality of Shoumen (2012)
- Yamaguchi University, Japan (2005, 2012, 2015, 2019)
- Administration of Moravský kras PLA, Blansko, Czech Republic (2012, 2015)
- Cave Administration of the Czech Republic (2012, 2015)
- Zespół Parków Krajobrazowych Województwa Śląskiego, Poland (2015, 2019)
- “Titan Zlatna Panega cement”, Bulgaria (2015, 2019)
- National Museum of Natural History - BAS, Sofia, Bulgaria (2015, 2019)