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Priority claimed from GB838327664Aexternal-prioritypatent/GB8327664D0/en
Priority claimed from GB848405224Aexternal-prioritypatent/GB8405224D0/en
Application filed by Albert Frederick WigleyfiledCriticalAlbert Frederick Wigley
Priority claimed from EP84306329Aexternal-prioritypatent/EP0138401B1/de
Application grantedgrantedCritical
Publication of ATE63999T1publicationCriticalpatent/ATE63999T1/de