@article{INTF_2003_90_a0,
     author = {Robert Osserman},
     title = {Preface},
     journal = {Itogi Nauki i Tekhniki. Seriya Sovremennye Problemy Matematiki. Fundamental'nye Napravleniya},
     pages = {9--12},
     year = {2003},
     volume = {90},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/INTF_2003_90_a0/}
}