theorem instCoeObjectAggregateMaterialEntity._proof_1
theorem instCoeObjectAggregateMaterialEntity._proof_1: ∀ (v : ta3nj1a4.ObjectAggregate), ta3nj1a4.MaterialEntity.Is (Subtype.val v)
theorem instCoeObjectAggregateMaterialEntity._proof_1
theorem instCoeObjectAggregateMaterialEntity._proof_1: ∀ (v : ta3nj1a4.ObjectAggregate), ta3nj1a4.MaterialEntity.Is (Subtype.val v)