Stephen Arthur Stills (born January 3, 1945) is an American musician, singer, and songwriter best known for his work with Buffalo Springfield, Crosby, Stills & Nash, and Manassas. As both a solo act and member of three successful bands, Stills has combined record sales of over 35 million albums. He was ranked number 28 in Rolling Stone's 2003 list of "The 100 Greatest Guitarists of All Time" and number 47 in the 2011 list. Stills became the first person to be inducted twice on the same night into the Rock and Roll Hall of Fame. According to Neil Young, "Stephen is a genius".
https://en.wikipedia.org/wiki/Stephen_Stills