1. Department of Mathematics, Faculty of Mathematics and Natural Sciences, Universitas Riau, Kota Pekanbaru 28292, Indonesia
2. Department of Mathematics, Faculty of Science and Technology, University of Jambi, Jambi City 36361, Indonesia
3. Department of Mathematics, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Jatinangor, Sumedang 45363, Indonesia
4. Research Center for Testing Technology and Standards, National Research and Innovation Agency, Jakarta 10340, Indonesia
5. Doctoral Program of Mathematics, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Sumedang 45363, Indonesia