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Jaroslav Kraft
Center of Biology, Geosciences and Environmental
Sciences, Faculty of Education, University of West Bohemia in Plzeň,
Klatovská 51, 306 19 Plzeň, Czech Republic
Michal Mergl
Center of Biology, Geosciences and Environmental
Sciences, Faculty of Education, University of West Bohemia in Plzeň,
Klatovská 51, 306 19 Plzeň, Czech Republic