@article{UM_1993_1_4_a17,
     author = {Calda, E.},
     title = {\v{C}{\'\i}sla komplexn\v{e} sdru\v{z}en\'a?},
     journal = {U\v{c}itel matematiky},
     pages = {48--49},
     year = {1993},
     volume = {1},
     number = {4},
     language = {cs},
     url = {http://geodesic.mathdoc.fr/item/UM_1993_1_4_a17/}
}