After reading L. Ron Hubbard's book Dianetics in 1968, jazz musician Chick Corea and Hubbard began corresponding to each other until Hubbard's death in 1986. The musician also had a guest spot on Hubbard's 1982 album Space Jazz: The Soundtrack of the Book Battlefield Earth. According to The Guardian, he also appeared on the 1986 album The Road To Freedom by using the vocals of L. Ron Hubbard prior to his death in 1986 and actor John Travolta. The publication described the lyrics "as rotten" with Travolta singing "Reality is me. Reality is you. Yeah Yeah Yeah." In 1993, Corea was banned from a concert in Stuttgart, Germany "as a propagandist for the Scientology sect."