TY JOUR TI ANALYSIS OF THE COST STRUCTURE OF TIMBER TRANSPORTATION AND THEIR SEASONAL DYNAMICS KW timber transportation KW logistic of the logging process KW machine productivity KW production seasonality JO Forestry Engineering Journal AU Mokhirev, A.P. AU Gerasimova, M.M. AU Pozdnyakova, M.O. PY 2020 IS 10 PB FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov