Lecture #20 looked at simple approaches to planning using STRIPS and some of the issues involved in combining planning and acting.
Notes are available in two formats:
This material is covered (in a lot more detail) in the textbook in Chapter 11, pages 375-395.
The original paper on the STRIPS approach was:
R. E. Fikes and N. J. Nilsson. STRIPS: A new approach to theorem proving in problem solving. Artificial Intelligence, 2:189--208, 1971