** FILE **Challenger Cassius Clay is shown in rare form as he signed to meet heavyweight boxing champion Sonny Liston, in this Nov. 6, 1963 file photo. A new book, "Ali Rap: Muhammad Ali the First Heavyweight Champion of Rap," proclaims Ali's verbal barrage was more than self-promotion, but sowed the seeds of hip-hop, which came into being in the `70s. (AP Photo/stf/FILE)