Dionysius of Alexandria
Patristic
d. A.D. 264
“There is, besides, another John mentioned in the Acts of the Apostles, with the surname Mark, whom Barnabas and Paul attached to themselves as companion, and of whom again it is said: "And they had also John to their minister." But whether this is the one who wrote the Revelation, I could not say. For it is not written that he came with them into Asia.”