@article{CTGDC_1998__39_1_63_0,
     author = {Pultr, A. and Sichler, J.},
     title = {Finite commutative monoids of open maps},
     journal = {Cahiers de Topologie et G\'eom\'etrie Diff\'erentielle Cat\'egoriques},
     pages = {63--77},
     publisher = {Dunod \'editeur, publi\'e avec le concours du CNRS},
     volume = {39},
     number = {1},
     year = {1998},
     mrnumber = {1615406},
     zbl = {0898.20045},
     language = {en},
     url = {http://www.numdam.org/item/CTGDC_1998__39_1_63_0/}
}