Erratum to: “Top-down Tree Transducers with Regular Look-ahead”

In Theorem 3.2 of my paper [1] it is shown thatDB-FST ⊂ DTR-FST, whereDB-FST is the class of deterministic bottom-up finite state tree transformations and DTR-FST is the class of deterministic top-down finite state tree transformations with regular look-ahead (and ⊂ denotes proper inclusion). One may then ask for a characterization of DB-FST in terms of dtr-fst. In Theorem 3.2 of [1] it is wrongly stated that DB-FST = ODTR-FST, whereODTR-FST is the class of one-state dtr-fst. The correct statement is that DB-FST = FTA ◦ ODTR-FST,