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Priority claimed from US06/777,061external-prioritypatent/US4690894A/en
Application filed by Advanced Mineral TechfiledCriticalAdvanced Mineral Tech
Priority claimed from EP85112810Aexternal-prioritypatent/EP0181497B1/de
Application grantedgrantedCritical
Publication of ATE51208T1publicationCriticalpatent/ATE51208T1/de