∀[T:Type]
MultiTree(T) ≡ lbl:Atom × if lbl =a "Node" then labels:{L:Atom List| 0 < ||L||} × ({a:Atom| (a ∈ labels)} ─→ MultiTr\000Cee(T))
if lbl =a "Leaf" then T
else Void
fi
{ ProveDatatypeExt }