Charles Ives' Symphony No. 3 "The Camp Meeting"

I just listened to the seventeenth disc of Neville Marriner and the Academy of St. Martin-in-the-Fields' The Argo Years for the first time.  It includes Charles Ives' Symphony No. 3 "The Camp Meeting."  I'd never heard this before, but I did recognize a melody at the very end of the first movement "Old Folks Gatherin'."  It took me awhile to figure out what it was, but I eventually discovered that it's an adaptation of the melody of "Azmon," written by Carl G. Gläser.  (Apparently, "Azmon" is often used for hymns.  I know it through "Awake, O Sleeper, Rise from Death," which I recorded back in April for a different musical project I'm doing [if I hadn't, it would have taken me a lot longer to identify this melody], and it's also used for "The Savior Calls; Let Every Ear.")

According to the liner notes for The Argo Years, Ives lived from 1874 to 1954, and my hymnal says that Gläser lived from 1784 to 1829.  So Ives is quoting Gläser's work rather than the other way around.

I don't know anything about Gläser or Ives, so I can't really comment on Ives' quoting Gläser.  The only thing I can do is note it.