• Macrooperators
  • Serializable subgoals
• Hierarchical planning
  • Assigning criticalities, ABSTRIPS
  • The monotonicity property
  • The ordered monotonicity property
  • Learning abstraction hierarchies

Craig A. Knoblock, Josh D. Tenenberg, and Qiang Yang. "Characterizing abstraction hierarchies for planning". In Proceedings of the Ninth National Conference on Artificial Intelligence (AAAI-91), Anaheim, CA, 1991. (postscript version).

• Describes criticalities, monotonicity properties

Richard E. Korf. "Planning as Search: A Quantitative Approach". Artificial Intelligence, Volume 33, Number 1, 1987.

• Describes macrooperators, serializability

Earl D. Sacerdoti. "Planning in a Hierarchy of Abstraction Spaces". Artificial Intelligence, Volume 5, Number 2, 1974.

• ABSTRIPS

Craig A. Knoblock. "Automatically Generating Abstractions for Planning". Artificial Intelligence, Volume 68, Number 2, 1994.

• Learning abstraction hierarchies