Public Function Add( _
    ByVal Plane As String _
) As 

public IAgVmVOCrossSectionPlane Add(
    string Plane
);

public: IAgVmVOCrossSectionPlane^ Add(
    String __gc ^ Plane
);

public IAgVmVOCrossSectionPlane add(
    String Plane
);

public: HRESULT Add(
    BSTR Plane,
    IAgVmVOCrossSectionPlane ** ppRetVal
);