Authors
Violeta Crai
Department of Mathematics, West University of Timişoara, Timişoara, Romania
Mihail Megan
Academy of Romanian Scientists, West University of Timişoara, Faculty of Mathematics and Computer Sciences, Timişoara, Romania
© 2020 Violeta Crai, Mihail Megan, published by West University of Timisoara
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.