New article: Ove Hansson, “AGM contraction is not reconstructible as a descriptor operation"

New article: Ove Hansson, “AGM contraction is not reconstructible as a descriptor operation", Journal of Logic and Computation 27(4):1133-1141. This is an investigation of the relationship between two operations in the logic of belief change, traditional contraction (giving up a belief) and the new operation of descriptor revision that is more general in several respects.