\begin{tabbing}
Feasible($D$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$\=($\forall$$i$:Id. Feasible(M($i$)))\+
\\[0ex]\& ($\forall$$l$:IdLnk, ${\it tg}$:Id. M(source($l$)).dout($l$,${\it tg}$) $\subseteq\rho$ M(destination($l$)).din($l$,${\it tg}$))
\\[0ex]\& ($\forall$$i$:Id. finite{-}type(\{$l$:IdLnk$\mid$ destination($l$) $=$ $i$ \& M(source($l$)) sends on link $l$ \}))
\-
\end{tabbing}