@article{UM_1994_2_4_a5,
     author = {Jaro\v{s}, Petr},
     title = {Didaktick\'y n\'apad},
     journal = {U\v{c}itel matematiky},
     pages = {26},
     year = {1994},
     volume = {2},
     number = {4},
     language = {cs},
     url = {http://geodesic.mathdoc.fr/item/UM_1994_2_4_a5/}
}