$\forall$$l$:IdLnk, ${\it dt}$:fpf(Id; ${\it tg}$.Type), ${\it tg}$:Id, $T$:Type.
\\[0ex]sqequal(fpf{-}cap(lnk{-}decl($l$; ${\it dt}$); Kind{-}deq; rcv($l$,${\it tg}$); $T$); fpf{-}cap(${\it dt}$; id{-}deq; ${\it tg}$; $T$))