Robert Silverberg Downward To The Earth – 1970 The Book Of Skulls – 1971 Dying Inside – 1972 The Iron Star – 1987 The Positronic Man – 1992 Travelers – 1999 The Millennium Express – 2000 A Piece of the Great World – 2005 ~~~~~~~~ Amazon Website goodreads Wikipedia Bibliography #robertsilverberg ABCDEFGHIJKLMNOPQRSTUVWXYZ