Evaluation of Hereford bulls by the quality of their offspring over various periods of growing their offspring under farm conditionsAlexey Zelenkov, Galina Zelenkova, Sergei Tresnitskii, Pavel Bykadorov, Natalia Volgina and Andrey MedvedevE3S Web Conf., 217 (2020) 09010DOI: https://doi.org/10.1051/e3sconf/202021709010