VERTCRS["IGN 1988 SM height",
    VDATUM["IGN 1988 SM"],
    CS[vertical,1],
        AXIS["gravity-related height (H)",up,
            LENGTHUNIT["metre",1]],
    USAGE[
        SCOPE["Geodesy, engineering survey, topographic mapping."],
        AREA["Guadeloupe - onshore - St Martin island."],
        BBOX[18.01,-63.21,18.17,-62.96]],
    ID["EPSG",5620]]