@misc{ARM_1998_34_1_a0,
     title = {Preface},
     journal = {Archivum mathematicum},
     year = {1998},
     volume = {34},
     number = {1},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ARM_1998_34_1_a0/}
}