@article{SMJ2_2015_41_4_a0,
     author = {Editors},
     title = {Preface},
     journal = {Serdica Mathematical Journal},
     publisher = {mathdoc},
     volume = {41},
     number = {4},
     year = {2015},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SMJ2_2015_41_4_a0/}
}