IP Library Granted Patent US 4,989,221
Granted Patent Utility
US 4,989,221 · App. 07/431,712

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Inventors: Shahid U. H. Qureshi, Fuyun Ling
Patented Case View Patent ↗
Granted: Jan 29, 1991 Filed: Nov 2, 1989
Inventors
Shahid U. H. Qureshi
Fuyun Ling
Assignee (at issue)
Codex Corporation

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Quick Facts
Patent No.
US 4,989,221
App. No.
07/431,712
Filed
1989-11-02
Granted
1991-01-29
Kind
A