**Author details**

Leon Dorozik, Tomasz Strąk and Ireneusz Miciuła\* Faculty of Economics, Finance and Management, University of Szczecin, Poland

\*Address all correspondence to: irekmic@wp.pl; ireneusz.miciula@usz.edu.pl

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
