1. Parallel non-binary planning in polynomial time;Bäckström,1991
2. Complexity results for SAS+ planning;Bäckström,1993
3. long version appeared as: Research Report, LiTH-IDA-R-93-34, Computer and Information Science, Linköping University, Sweden
4. PHI—a logic-based tool for intelligent help Systems;Bauer,1993
5. The logical language for planning LLP;Biundo,1994