@article{UM_1993_1_1_a6,
     author = {Hejn\'y, Milan},
     title = {PME a {NCTM} konferencie 1992},
     journal = {U\v{c}itel matematiky},
     pages = {13--17},
     year = {1993},
     volume = {1},
     number = {1},
     language = {sk},
     url = {http://geodesic.mathdoc.fr/item/UM_1993_1_1_a6/}
}