Denise Sullivan has written on music for 20 years, in print and on the web. Her books are The White Stripes: Sweethearts of the Blues, R.E.M.—Talk About the Passion, and Rip It Up! Rock ’n’ Roll Rulebreakers. She's the Origin of Song columnist for Crawdaddy! Her fourth book, Keep on Pushing: Black Power Music From Blues to Hip-Hop, concerns 50 years of liberation music.