@article{ITA_1997__31_3_291_0,
     author = {Hakala, Ismo and Kortelainen, Juha},
     title = {Polynomial size test sets for commutative languages},
     journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications},
     pages = {291--304},
     publisher = {EDP-Sciences},
     volume = {31},
     number = {3},
     year = {1997},
     mrnumber = {1483261},
     zbl = {0889.68091},
     language = {en},
     url = {http://www.numdam.org/item/ITA_1997__31_3_291_0/}
}