UIAPI - add Base Refecences to a Form

Hi all, is there a way to set the values of the BaseType, BaseRef, BaseKey and BaseRow using the UIAPI directly?

If a do a copy from in a marketing document, SAP fill in the Base References, but if i try to set them but does not work:

((SAPbouiCOM.EditText)POMatrix.Columns.Item("44").Cells.Item(1).Specific).Value = "3";

((SAPbouiCOM.EditText)POMatrix.Columns.Item("45").Cells.Item(1).Specific).Value = "3";

((SAPbouiCOM.EditText)POMatrix.Columns.Item("46").Cells.Item(1).Specific).Value = "0";

Thank you.