See this web page: The Danish Peace Academy: Greenham Common Women's Peace Camp Songbook. It's got the lyrics, sheet music, some background info, and a sound file. This is what's printed:

YOU CAN'T KILL THE SPIRIT – "a spiritual - also a round"
Naomi Littlebear Morena

You can't kill the Spirit
She is like a mountain
Old and strong
She goes on an on and on.

However, the recording is much longer and more complex. And they don't sing it as a round.