00259nam a2200109Ia 4500008004100000082001300041100000900054245003200063250000900095260003600104300000900140240913s9999||||xx |||||||||||||| ||und||  a530  ENC  aNULL 4aThe Encyclopedia of Pfysics  aNULL  bCBS PublishersaNew Delhic1987  a1377