May be implemented as a single transformation using position vector 7-parameter geocentric transformation method with parameter values dX=+199m dY=+931m dZ=+318.9m rX=rY=0 sec rZ=+0.814 sec dS=-0.38 ppm.
Various oil company sources.
2020-03-14
Geodesy.
See CRS code 4131 for recommended coordinate axis representation for the human interface.
Cambodia - mainland onshore; Vietnam - mainland onshore.
Ellipsoidal 2D CS. Axes: latitude, longitude. Orientations: north, east. UoM: dec deg