Five off the top of my head:
Jauchzet, frohlocket!
In the Bleak Mid-Winter
Once in Royal David's City
Es ist ein Ros entsprungen
God Rest You Merry, Gentlemen
Haven't listened to any pop Christmas at all this year. Didn't mean to, it just worked out that way.
AC/DC - Mistress For Christmas
Tiny Tim - Santa Claus Has Got the AIDS This Year
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