TY JOUR TI OPTIMIZATION OF SOWN AREA STRUCTURE OF CROPS BY ECONOMIC AND MATHEMATICAL MODELING: PRACTICAL ASPECT KW modeling KW land-use efficiency KW predictive structure. JO Vestnik of Kazan State Agrarian University AU Nuretdinova, Y.. AU Nuretdinov, I.. AU Khasyanov, O.. PY 2015 IS 10 PB Kazan state agrarian University