@article{CMUC_1981_22_1_a15,
     author = {Zaj{\'\i}\v{c}ek, Lud\v{e}k},
     title = {On the symmetry of {Dini} derivates of arbitrary functions},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {195--209},
     year = {1981},
     volume = {22},
     number = {1},
     mrnumber = {609947},
     zbl = {0462.26003},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1981_22_1_a15/}
}