Authors
Wacława Starzyńska
waclawa.starzynska@poczta.umcs.lublin.pl
Maria Curie-Sklodowska University, Faculty of Economics, Chair of Statistics and Econometrics, Lublin, Poland
waclawa.starzynska@poczta.umcs.lublin.pl
© 2019 Wacława Starzyńska, published by University of Szczecin
This work is licensed under the Creative Commons Attribution-ShareAlike 4.0 License.