Bulgakov, Volodymyr, Hristo Beloev, Ivan Holovach, Vladimir Kročko, Ladislav Nozdrovicky, and Pavol Findura. 2018. “The Most Complex Theory of the Symmetric Impact of the Vibrating Digging Working Tool on the Sugar Beet Root”. Journal of Agricultural Engineering 49 (4), 207-19. https://doi.org/10.4081/jae.2018.795.