00513naa#a2200169#i#450# EN\\bibl\1085 20240428015206.7 2073-0462 20140113b2014####ek#y0engy0150####ca RUS RU Spring wheat productivity forecasting in the forest steppe zone of Volga by least squares method Journal article Kazan Kazan state agrarian University 2014 6 с. Journal article local Avvakumov Oleg naukaru.ru