CBU International Conference on Innovations in Science and Education 2021. Conference. International Conference on Innovations in Science and Education (Natural Sciences and ICT) : Proceedings of CBU in Economics and Business. Vol. 2. 1. vydání. Prague : CBU Research Institute, 2021. [154 s.]. Available on Internet: <https://ojs.cbuic.cz/index.php/pns> ISBN 978-80-908061-4-6. ISSN 2695-0693 (Online).