Dunn, J. Michael: The Frame Problem and Relevant Prediction. Code: [Dunn90A].
Geffner, Hector, and Judea Pearl: A Framework for Reasoning with Defaults. Code: [Geffner90A].
Schubert, Len: Monotonic Solution of the Frame Problem in the Situation Calculus: An Efficient Method for Worlds with Fully Specifies Actions. Code: [Schubert90A].
Nute, Donald: Defeasible Logic and the Frame Problem. Code: [Nute90A].