Truong, N.N. and Nhac, T.V. 2017. Determination of the constant <i>W</i>_o for local geoid of Vietnam and it’s systematic deviation from the global geoid. Vietnam Journal of Marine Science and Technology. 17, 4B (Dec. 2017), 138–144. DOI:https://doi.org/10.15625/1859-3097/17/4B/13001.