@article{PMFA_1978_23_3_a4,
     author = {Sgall, Petr},
     title = {Matematick\'y popis p\v{r}irozen\'ych jazyk\r{u}},
     journal = {Pokroky matematiky, fyziky a astronomie},
     pages = {140--148},
     year = {1978},
     volume = {23},
     number = {3},
     zbl = {0387.68073},
     language = {cs},
     url = {http://geodesic.mathdoc.fr/item/PMFA_1978_23_3_a4/}
}