- 1969: Across a Billion Years, Dial Hard cover book, 249 pp.
- 1977: Across a Billion Years, Gollancz Hard cover book
- 1979: Across a Billion Years, Magnum Mass market paperback
- 1980: Across a Billion Years, Berkley Mass market paperback
- 1982: Nach all den Jahrmilliarden, Moewig Mass market paperback, in German
- 1983: Across a Billion Years, Tor Mass market paperback, ISBN 0-81255450-7, 249 pp.
- 1983: Un Milliard d'années plus tard, Superlights Mass market paperback, in French
- 1986: Across a Billion Years, Tor Mass market paperback, 249 pp.
- 1999: Across a Billion Years, Peanut Press Online
- 2002: Человек в лабиринте, Eksmo Эксмо Hard cover book, ISBN 5040094647, 654 pp., in Russian as Через миллиард лет
(from Tor 1983)
Scattered throughout the globe of human-occupied space is evidence of a civilization that bestrode the galaxy before humanity was born. Now, a strange device has been discovered that shows the details of that great civilization. The details include a star map and hints that the High Ones are not extinct after all.
The map beckons, and humans, being what they are, will follow. To the next great step in human destiny—or ultimate disaster.
[None on record]