@article{UM_1998__6_4_a6,
     author = {Ku\v{r}ina, Franti\v{s}ek},
     title = {Heron\r{u}v d\r{u}kaz {Heronova} vzorce},
     journal = {U\v{c}itel matematiky},
     pages = {234--237},
     publisher = {mathdoc},
     volume = {06},
     number = {4},
     year = {1998},
     language = {cz},
     url = {http://geodesic.mathdoc.fr/item/UM_1998__6_4_a6/}
}