@article{CMUC_1978_19_1_a11,
     author = {Kadle\v{c}ek, Ji\v{r}i},
     title = {Closure conditions in the nets},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {119--133},
     year = {1978},
     volume = {19},
     number = {1},
     mrnumber = {492374},
     zbl = {0389.51004},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1978_19_1_a11/}
}