Justification of the optimal annual load on the tractor providing for its parameters stress on the formed cropCamill A. Khafizov, Ramil N. Khafizov, Azat A. Nurmiev and Ilgiz G. GalievBIO Web Conf., 17 (2020) 00022DOI: https://doi.org/10.1051/bioconf/20201700022