About this article
Published Online: Dec 11, 2014
Page range: 15 - 18
Received: Jan 25, 2014
DOI: https://doi.org/10.2478/aupcsm-2014-0002
© by Kamila Kliś-Garlicka
This work is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License.
Kamila Kliś-Garlicka
Institute of Mathematics University of Agriculture Balicka 253c 30-198 Kraków Poland