MARKOVICH, K., and M. MAKAROVA. “ANALYSIS OF OBTAINING NORMAL HEIGHTS POINTS OF THE EARTH’S SURFACE USING DATA FROM SATELLITE MEASUREMENTS AND MODELS OF THE GEOID”. Vestnik of Polotsk State University. Part F. Constructions. Applied Sciences, no. 8, July 2016, pp. 139-42, https://journals.psu.by/constructions/article/view/1393.