Larysa K. Veselova, Roza T. Bexeitova, Khaini-Kamal M. Kassymkamova, Kulzada Zh. Duisebaeva, Rahat O. Turapova, Saltanat O. Tumazhanova, Omirzhan Z. Taukebaev
INT ELECT J MATH ED, Volume 11, Issue 7, 2016, 1987-2001