I found the handwritten manuscript of "Libera me Domine" in my country Latvia in one of Riga's Church's library, where Chopin was indicated as the composer of this score. But nothing other info I didn't find more. I'm not sure that he is right composer of this score, too. It looks more closer to Joseph Gruber, but it was so indicated on that manuscript, written by one old and famous organist of that Church, who now is died. I can't verify this question, because there are many people, who ask me about it... Sorry, but I have no more other information about this piece of music. If someone would be able to find the different composer of the same music I'm ready to change it in all sites where I put it. Any accompaniment I couldn't find.
why does the international score project's website look so much like wikipedia's?