@article{Ryzhkova2015plane,
author={Ryzhkova, E.. and Sitnik, S..},
title={Plane curves which generalize classic quadrics},
journal={Actual directions of scientific researches of the XXI century: theory and practice},
publisher={FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov},
year={2015},
pages={364-368},
volume={3},
issue={9},
}