w{-}sender($w$; $e$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$$<$source(lnk(w{-}ekind($w$; $e$))), mu($\lambda$$t$.w{-}match($w$; lnk(w{-}ekind($w$; $e$)); $t$; w{-}time($w$; $e$)))$>$