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22Finite Axiomatizability of Transitive Modal Logics of Finite Depth and Width with Respect to Proper-Successor-EquivalenceReview of Symbolic Logic 1-14. forthcoming.This paper proves the finite axiomatizability of transitive modal logics of finite depth and finite width w.r.t. proper-successor-equivalence. The frame condition of the latter requires, in a rooted transitive frame, a finite upper bound of cardinality for antichains of points with different sets of proper successors. The result generalizes Rybakov’s result of the finite axiomatizability of extensions of$\mathbf {S4}$of finite depth and finite width.