It's another name for the prelude, op. 31 no. 8, and Billaudot published it in an edition of Alkan works edited by Ronald Smith in 1979. They're in Paris. May not still be in print, though a number of libraries have it. Hrm. As to a more recent edition... Masters Music, in Boca Raton Florida, published all 25 Preludes op. 31 (including, therefore, la Chanson) in 1997. Hope this is still in print and that this information is useful to you. Sorry, I don't check these boards as often as I might, took me a while to respond...