Authors
Iwona Włoch
Department of Discrete Mathematics, Rzeszow University of Technology, Rzeszow, Poland
Andrzej Włoch
Department of Mathematical Modeling, Rzeszow University of Technology, Rzeszow, Poland
© 2020 Iwona Włoch, Andrzej Włoch, published by Slovak Academy of Sciences, Mathematical Institute
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.