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Priority claimed from FR759144Aexternal-prioritypatent/FR72986E/fr
Priority claimed from FR771206Aexternal-prioritypatent/FR73886E/fr
Application filed by Fr D Incandescense Par Le GasfiledCriticalFr D Incandescense Par Le Gas
Application grantedgrantedCritical
Publication of BE574400RpublicationCriticalpatent/BE574400R/fr