$\forall$${\it ds}$:(Id$\rightarrow$Type), ${\it da}$:(Id$\rightarrow$Knd$\rightarrow$Type), $A$, $B$:Type.
\\[0ex]($A$ $\subseteq$r $B$) $\Rightarrow$ (Interface(${\it ds}$;${\it da}$;$A$) $\subseteq$r Interface(${\it ds}$;${\it da}$;$B$))