Joe,
   I Googled it, which led me back to Mudcat. But it wasn't easy.
   Here's how I did it:
   I Googled "When Mama Parks sat down." No hits.
   I tried "When Mamma Parks sat down." No hits.
   Then I spelled it "When Momma Parks sat down." Voila! "The Ballad of Momma Parks" at good old Mudcat.
   You know that Rosa Parks lives in your old stomping grounds, Detroit, yes? She's in her 90s, has Alzheimer's and is much bveloved.