"Definitive version" - no such animal for a Sydney Carter song.

"That word final worries me. There is nothing final in the songs I write, not even the words, the rhythym and the melody. This is not an oversight; I would like them to keep on growing, like a tree. They have a form, I hope; so does a tree. But it is not fixed and final. It must develop acoording to the time and place..." (From introduction to Green Print for Song.