@article{INTF_1991_69_a0,
     author = {W. Bart and Raghavan Narasimhan},
     title = {Preface},
     journal = {Itogi Nauki i Tekhniki. Seriya Sovremennye Problemy Matematiki. Fundamental'nye Napravleniya},
     pages = {5},
     year = {1991},
     volume = {69},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/INTF_1991_69_a0/}
}