1. Siedlce University of Natural Sciences and Humanities Faculty of Sciences 3 Maja 54 08-110 Siedlce Poland
2. Cardinal Stefan Wyszyński University in Warsaw Faculty of Mathematics and Natural Sciences K. Woycickiego 1/3 01-938 Warszawa Poland
3. Jan Kochanowski University of Kielce Faculty of Natural Sciences Uniwersytecka 7 25-406 Kielce Poland