Items Authored by Robert Abbott
- Ultima. Robert Abbott's Ultima page. By Robert Abbott.
- Ultima Problem #3. The 3rd in a series of Ultima puzzles. By Robert Abbott.
- Ultima Problem #9. The 9th in a series of Ultima puzzles. By Robert Abbott.
- Abbott's New Card Games (book information). Information on a book describing Ultima, and eight card games. By Robert Abbott.
- Abbott, Robert. Logic Mazes: Website of Robert Abbott. Author: Robert Abbott.