When Was the First Reference to the Franks?

When is the first reference to the franks? That's a question that a lot of people type into their search engines. We are very reliant roman authors for these early centuries, so what we know about these groups is handed down to us through a roman lens. So it's very difficult to say anything about them with complete certainty because we don't know whether these depictions reflect the way that frankish people would have thought about themselves.