www.google.com.auhttp://www.google.com.au/patents/US3319119?utm_source=gb-gplus-sharePatent US3319119 - METAL VAPOR SPECTRAL LAMP WITH MERCURY AND A METAL HALIDE AT SUBATMOSFHERIC PRESSURE
METAL VAPOR SPECTRAL LAMP WITH MERCURY AND A METAL HALIDE AT SUBATMOSFHERIC ...
