1. Director of Institute of Geodesy, Dept. of Higher Geodesy and Astronomy, Lviv Polytechnic National Univ., 12, Stepan Bandera St., Lviv 79013, Ukraine (corresponding author).
2. Associate Professor, Dept. of Higher Geodesy and Astronomy, Lviv Polytechnic National Univ., 12, Stepan Bandera St., Lviv 79013, Ukraine.