@article{ITA_1980__14_2_225_0,
     author = {Prodinger, Helmut},
     title = {Topologies on free monoids induced by closure operators of a special type},
     journal = {RAIRO. Informatique th\'eorique},
     pages = {225--237},
     publisher = {EDP-Sciences},
     volume = {14},
     number = {2},
     year = {1980},
     mrnumber = {581679},
     zbl = {0444.68077},
     language = {en},
     url = {http://www.numdam.org/item/ITA_1980__14_2_225_0/}
}