Ibrahim Yahaya, Salissou, El Hassan El Brirchi, and Driss El Azzab. “Impact of Datum Transformation on Local Variations of Geometric Geoid in Niger”. Geodesy and Cartography 43, no. 4 (December 21, 2017): 147-157. Accessed November 8, 2024. https://gc.vgtu.lt/index.php/GAC/article/view/1699.