About this article
Published Online: Dec 22, 2018
Page range: 263 - 266
DOI: https://doi.org/10.2478/mgrsd-2000-090131
Keywords
© 2018 Jerzy Siwek, published by Sciendo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.
Siwek, Jerzy