1. Rush Hour is PSPACE-complete, or “Why you should generously tip parking lot attendants”
2. The mathematical puzzles of Sam Loyd, Dover Publications, Mineola, NY, 1959.
3. , Computers and intractability: A guide to the theory of NP-completeness, Freeman and Company, New York, 1979.
4. Harnessing computational resources for efficient exhaustive search, PhD Thesis, Swiss Federal Institute of Technology, Zürich, 1995.