@article{Popov2014status,
author={Popov, M.. and Leparov, M.N.},
title={Status and Trends of Geometrical-Graphic Training as a Component of Engineering Education in Bulgaria},
journal={Geometry & Graphics},
publisher={INFRA-M Academic Publishing LLC.},
year={2014},
pages={22-29},
volume={2},
issue={1},
}