@article{ITA_1999__33_4-5_447_0,
     author = {Corradini, Flavio and De Nicola, Rocco and Labella, Anna},
     title = {A finite axiomatization of nondeterministic regular expressions},
     journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications},
     pages = {447--465},
     publisher = {EDP-Sciences},
     volume = {33},
     number = {4-5},
     year = {1999},
     mrnumber = {1748666},
     zbl = {0945.68122},
     language = {en},
     url = {http://www.numdam.org/item/ITA_1999__33_4-5_447_0/}
}