is mentioned by

Def interface-check(D;l;tg;T) == T r M(destination(l)).din(l,tg)	[interface-check]
Def d-feasible(D) Def == (i:Id. Feasible(M(i))) Def == & (l:IdLnk, tg:Id. Def == & (M(source(l)).dout(l,tg) r M(destination(l)).din(l,tg)) Def == & (i:Id.  Def == & (finite-type({l:IdLnk Def == & (finite-type({| destination(l) = i & M(source(l)) sends on link l }))	[d-feasible]

In prior sections: mb event system 2 mb event system 3

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