Corollary 1
Tag 0612, permanent. Cite it as [Bourbaki, Tag 0612].
Algebra, chapter III, § 4. Tensor products of algebras
In the notation of Proposition 10, suppose further that F is a graded A-algebra of type and that each is a graded algebra homomorphism relative to ; then is a graded algebra homomorphism.
This follows immediately from the definition of and the fact that
It is therefore seen that is also a solution of another universal mapping problem, where this time is the species of graded A-algebra structure of type , the morphisms being graded algebra homomorphisms of type and the -mappings the mappings , where, in addition to conditions (26), it is assumed that is a graded algebra homomorphism relative to .
Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.