“…Isberner [36] shows that these descendants of L * can be described in a single, general framework. 1 Variations of L * have also been used as a basis for learning extensions of DFAs such as Mealy machines [48], I/O automata [2], non-deterministic automata [16], alternating automata [6], register automata [1,17], nominal automata [46], symbolic automata [40,7], weighted automata [14,11,30], Mealy machines with timers [64], visibly pushdown automata [36], and categorical generalisations of automata [62,29,12,18]. It is fair to say that L * -like algorithms completely dominate the research area of active automata learning.…”