Rational placement of grain production – the basis for ensuring food securityGuzaliya Klychova, Alsou Zakirova, Ilnur Safiullin, Zufar Zakirov, Shaukat Khusainov and Galina ZakharovaE3S Web Conf., 175 (2020) 08013DOI: https://doi.org/10.1051/e3sconf/202017508013