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Priority claimed from GB868614621Aexternal-prioritypatent/GB8614621D0/en
Application filed by Schlumberger Ind LtdfiledCriticalSchlumberger Ind Ltd
Priority claimed from EP87305236Aexternal-prioritypatent/EP0253499B1/de
Application grantedgrantedCritical
Publication of ATE82357T1publicationCriticalpatent/ATE82357T1/de