00886nam0-22003131i-450-9900011100004033210-582-00466-7000111000FED01000111000(Aleph)000111000FED0100011100020000920d1990----km-y0itay50------baengFurther Advances in Twistor TheoryLionel J. Mason & L.P. Hughston (Editors)EssexLongman1990Pitman research notes in mathematics series231RelativitàGravità530.11Mason,Lionel J.53055Hughston,Lane PalmerITUNINARICAUNIMARCBK99000111000040332123-21318522FI1FI1Further Advances in Twistor Theory337902UNINAING01