TY JOUR TI ANGLE VARIATION RANGE OF THE MOLAR TEETH CHEWING SURFACE PATTERN OF THE NORTHERN RED-BACKED VOLE ON THE SAKHALIN ISLAND KW northern red-backed vole KW pattern angle KW variation KW molar teeth chewing surface KW the Sakhalin Island JO Bulletin of KSAU AU Donchenko, I.V. AU Senchik, A.V. PY 2012 IS 0 PB Krasnoyarsk State Agrarian University