Kholmat M. Shadimetov
Institute of Mathematics, National University of Uzbekistan, Tashkent, Uzbekistan
Tashkent Institute of Railway Engineers, Tashkent, Uzbekistan
Abdullo R. Hayotov
Institute of Mathematics, National University of Uzbekistan, Tashkent, Uzbekistan
Azamov S. Siroj
Institute of Mathematics, National University of Uzbekistan, Tashkent, Uzbekistan