VERTCRS["Yellow Sea",
    VDATUM["Yellow Sea 1956"],
    CS[vertical,1],
        AXIS["gravity-related height (H)",up,
            LENGTHUNIT["metre",1]],
    USAGE[
        SCOPE["Geodesy, engineering survey."],
        AREA["China - onshore and offshore."],
        BBOX[16.7,73.62,53.56,134.77]],
    ID["EPSG",5704]]