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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 \}$\rightarrow$Prop).
\-\\[0ex][$e_{1}$,$e_{2}$]$\sim$([$a$,$b$].$Q$($a$,$b$))+ $\Rightarrow$ $e_{1}$ $\leq$ $e_{2}$ 
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