“There’s stuff with Freddie and David singing together,” Hince told The Guardian. “Proper full-length rock ’n’ roll tracks. Raw, but good. They just started knocking things around. They did cover versions, a few of their own things. They came back the next day and recorded what eventually became ‘Under Pressure.’ But there were other things recorded which were never finished or mixed. David did vocals which ended up not being used. So somewhere there is an archive. I was in the studio with them. It was all quite spontaneous. I can categorically say I know that there were complete tracks. Not mixed tracks, but fully formed songs. Does it belong to the David Bowie estate or to Queen? That’s probably part of reason these things have never come to light.” Queen guitarist and songwriter Brian May corroborated the roadie’s claims in an interview with Mojo to promote his new book, Queen in 3-D. May told Mojo drummer Roger Taylor invited Bowie to Montreaux and the musicians’ “mutual admiration” led to the a series of jams and recording sessions. According to May, “Freddie and David locked horns” in the studio during the sessions. “Sparks fly and that’s why it turned out so great. Not all of what we did in those sessions has ever come to light, so there’s a thought.” The single “Under Pressure” reached number one in the UK singles chart, and number 29 on the U.S. charts. The song was included on Queen’s 1982 album Hot Space. It went back into the top 50 after Bowie’s death.  David Bowie: I Was There will hit bookshelves on July 21.