Ignatz answered Friday November 30 2007, 12:26 pm: Chaeck out cdpl.org and musicaviva.org. Both sites offer free sheet music in a variety of styles and arrangements. One song I can think of offhand is "Novus Miles Sequitur". It's a medieval hymn, written for three voices in close harmony (organon). It's usually done by two tenors and a baritone, but you could easily do it for two sopranos and an alto.
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