About this article
Published Online: Jan 03, 2019
Page range: 77 - 84
DOI: https://doi.org/10.2478/aucft-2018-0015
Keywords
© 2018 Emil Hadzhikolev et al., published by Sciendo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.
Hadzhikolev, Emil
Plovdiv University “Paisii Hilendarski”, Department of Mathematics and InformaticsBulgaria
Hadzhikoleva, Stanka
Plovdiv University “Paisii Hilendarski”, Department of Mathematics and InformaticsBulgaria