This one's more subtle, as it doesn't refer to the songs *as songs*, but simply incorporates their names into the lyrics:

The Grateful Dead's "Uncle John's Band" mentions several oldtime/American trad songs and tunes. "Buckdancer's Choice" and "A Story the Crow Told Me" are the ones that come to my mind, but there may be more. Uncle John, supposedly, is John Cohen of the New Lost City Ramblers, who Garcia crossed paths with several times in the early 1960's.