@article{VM_2014_16_1_a1,
     author = {Valentina Kosti\'c and Tanja Sekuli\'c},
     title = {Extreme {Values} of {Function} in {GeoGebra} {Style}},
     journal = {Visual Mathematics},
     publisher = {mathdoc},
     volume = {16},
     number = {1},
     year = {2014},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/VM_2014_16_1_a1/}
}