VHRC, chapter 6 (The inheritance relation), page 81

     Rename Clause rule

     It is valid to use `old_name' as first element  of  a
     Rename_pair, appearing in the Rename subclause of the
     Parent clause for `B' in a class `C', if and only  if
     the following five conditions are satisfied:

        1 `old_name' is the final name  of  a  feature  of
          `B'.

        2 `old_name' does not appear as the first  element
          of  any  other  Rename_pair  in  the same Rename
          subclause.

        3 `new_name' and `old_name' are different.

        4 If renaming into a prefix, original feature must
          have a result and no argument.

        5 If renaming into an infix, original feature must
          have a result and one argument.

