Luyen, B. K. (2014). REFINING GEOIDAL HEIGHTS COMPUTED BY FULLY-NORMALISED SPHERICAL HARMONICS COEFFICIENTS OF THE EARTH GRAVITATIONAL MODEL EGM2008 BY ADJUSTMENT OF COMBINED GPS/LEVELLING/GEOID NETWORK. Vietnam Journal of Earth Sciences, 36(2), 169–174. https://doi.org/10.15625/0866-7187/36/2/4498