Authors
Rafieh Razavi Nazari
Faculty of Mathematics, K. N. Toosi University of Technology, Tehran
Shaban Ghalandarzadeh
Faculty of Mathematics, K. N. Toosi University of Technology, Tehran
© 2019 Rafieh Razavi Nazari, Shaban Ghalandarzadeh, published by Sapientia Hungarian University of Transylvania
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.