Premise: Tony Sanchez, also known as Spanish Tony (died 2000), was a British photographer of Spanish ancestry. He worked as Keith Richards' assistant for eight years and co-wrote with John Blake a bestselling memoir about this time, entitled "Up and Down with the Rolling Stones: My Rollercoaster Ride with Keith Richards" (1979).
Hypothesis: Tony Sanchez was an bestselling author and photographer for the Rolling Stones, which he wrote about in his memoir with co-write John Blake, entitled "Up and Down with the Rolling Stones: My Rollercoaster Ride with Keith Richards".