. . . . . . "48"^^ . . . "Strings and symmetries : proceedings of the G\u00FCrsey Memorial Conference I held at Istanbul, Turkey, 6-10 June 1994 / [edited by] G\u00FClen Akta\u015F, Cihan Sa\u00E7lio\u011Flu, Meral Serdaro\u011Flu / Berlin [etc.] : Springer" . . . . . .