Gabrielyan, V.P. “ON A LINEARIZED COVERINGS OF A CUBIC HOMOGENEOUS EQUATION OVER A FINITE FIELD. UPPER BOUNDS”. Proceedings of the YSU A: Physical and Mathematical Sciences, vol. 52, no. 3 (247), Dec. 2018, pp. 180-9, doi:10.46991/PYSU:A/2018.52.3.180.