@article{ITA_1981__15_2_149_0,
     author = {Straubing, Howard},
     title = {Relational morphisms and operations on recognizable sets},
     journal = {RAIRO. Informatique th\'eorique},
     pages = {149--159},
     publisher = {EDP-Sciences},
     volume = {15},
     number = {2},
     year = {1981},
     mrnumber = {618452},
     zbl = {0463.20049},
     language = {en},
     url = {http://www.numdam.org/item/ITA_1981__15_2_149_0/}
}