Authors
Iulia-Elena Hirica
Faculty of Mathematics and Computer Science, University of Bucharest, Bucharest, Romania
Cristina-Liliana Pripoae
Department of Applied Mathematics, The Bucharest University of Economic Studies, Bucharest, Romania
Gabriel-Teodor Pripoae
Faculty of Mathematics and Computer Science, University of Bucharest, Bucharest, Romania
Vasile Preda
“Gheorghe Mihoc-Caius Iacob” Institute of Mathematical Statistics and Applied Mathematics of Romanian Academy, 2, Bucharest, Romania
“Costin C. Kiritescu” National Institute of Economic Research of Romanian Academy, Bucharest, Romania
Faculty of Mathematics and Computer Science, University of Bucharest, Bucharest, Romania
