00429nam a2200133Ia 4500003000900000008004100009040001600050080001500066100002100081245010100102260003500203300001600238650004100254IN-BaIIA211028s9999    xx            000 0 eng d  cIIA Library  a550.3bBRU  aBruckshaw, J McG 0aMagnetic variometers of the schmidt typebtheir full use and maintenancecJohn McGarva Bruckshaw  aLondonbHilger and Wattsc1954  aviii, 115p.  aAstronomy and Astrophysics Thesaurus