Gets and sets the vertical coordinate system wkt
to be used to select the source spatial reference for the
TransformationInfo object (used to populate a table row).
The SourceVcsWkt is optional. The default is null. The SourceWkt should also be defined if a SourceVcsWkt is defined. If the SourceWkt and the SourceVcsWkt are set, then the corresponding SourceSpatialReference with that wkt and vcsWkt will be selected for the TransformationInfo object. Note: only one of: o SourceSpatialReference o SourceWkid, and SourceVcsWkid if applicable o SourceWkt, and SourceVcsWkt if applicable need be set. If the SourceSpatialReference is set, Wkids and Wkts are ignored. If the SourceSpatialReference is null, then Wkids are used. If the Wkids are 0 (or less), then the Wkts are used.