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