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Application filed by Elettrotecnica Varco S R LfiledCriticalElettrotecnica Varco S R L
Priority to IT21162/81ApriorityCriticalpatent/IT1137132B/en
Publication of IT8121162A0publicationCriticalpatent/IT8121162A0/en
Application grantedgrantedCritical
Publication of IT1137132BpublicationCriticalpatent/IT1137132B/en