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$\forall$\=${\it es}$:ES, $e_{1}$:E, $e_{2}$:\{$e$:E$\mid$ loc($e$) = loc($e_{1}$) $\in$ Id\} ,\+
\\[0ex]$Q$:(\{$e$:E$\mid$ loc($e$) = loc($e_{1}$) $\in$ Id\} $\rightarrow$\{$e$:E$\mid$ loc($e$) = loc($e_{1}$) $\in$ Id\} $\rightarrow\mathbb{P}$).
\-\\[0ex][$e_{1}$,$e_{2}$]$\sim$([$a$,$b$].$Q$($a$,$b$))+ $\Rightarrow$ $e_{1}$ $\leq$loc $e_{2}$ 
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