@article{ZR_2015_18_26_a0,
     author = {Silvia Ghilezan},
     title = {Preface},
     journal = {Zbornik radova},
     pages = {5 },
     publisher = {mathdoc},
     volume = {18},
     number = {26},
     year = {2015},
     url = {http://geodesic.mathdoc.fr/item/ZR_2015_18_26_a0/}
}