Protein composition and grain quality of spring soft wheat (triticumaestivuml.) depending on the level of nitrogen nutrition and pytoregulators use in case of cultivation on sod-podzol medium loamy soil // Izvestia of Timiryazev - Academy: Scientific-theoretical Journal of the Russian State Agrarian University - Moscow Agricultural Academy named after K.A. Timiryazev. – 2013. – Вып. special issue