If you choose, you can allow Click! to put the function to function
     and the module to fuction cross reference data into each of your
     source code modules.

     FUNCTION_REF_INTO_SOURCE=YES   ( module to function )

     FUNCTION_XREF_INTO_SOURCE=YES  ( function to function )

     TABLE_XREF_INTO_SOURCE=YES     ( table in module )

     INDEX_XREF_INTO_SOURCE=YES     ( index in module )