The Dual DFA Learning Problem: Hardness Results for Programming by Demonstration and Learning First-Order Representations (Extended Abstract).

William W. Cohen The Dual DFA Learning Problem: Hardness Results for Programming by Demonstration and Learning First-Order Representations (Extended Abstract). 29-40 1996 conf/colt/1996 COLT http://doi.acm.org/10.1145/238061.238066 db/conf/colt/colt1996.html#Cohen96