Doukas ID, Ampatzidis D, Kampouris V. THE VALIDATION OF THE TRANSFORMATION BETWEEN AN OLD GEODETIC REFERENCE FRAME AND A MODERN REFERENCE FRAME, BY USING EXTERNAL SPACE TECHNIQUES SITES: THE CASE STUDY OF THE HELLENIC GEODETIC REFERENCE SYSTEM OF 1987. BCG [Internet]. 25º de setembro de 2017 [citado 29º de abril de 2026];23(3). Disponível em: https://ojs.homologa.ufpr.br/bcg/article/view/55432