hatsoff

Paul, who was an associate of Peter, wrote what is probably the earliest extant Christian literature. The authors of Hebrews, Mark and Luke almost certainly lived early enough to have known an Apostle. The authors of the Didache, James, 1 Peter, 2 Thessalonians, Ephesians and Barnabas may also have had some personal contact with Peter and/or Paul, though in each individual case that seems unlikely.

I think it's fair to say that a number of early Christian authors all knew one of the original Apostles, but it's difficult to determine which of them had that honor.