IP Library › Granted Patent US 4,999,920
Granted Patent Utility
US 4,999,920 · App. 07/363,681

Surveying of boreholes

Inventors: Anthony Russell, Michael K. Russell
Patented Case View Patent ↗
Granted: Mar 19, 1991 Filed: Jun 9, 1989
Inventors
Anthony Russell
Michael K. Russell

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Quick Facts
Patent No.
US 4,999,920
App. No.
07/363,681
Filed
1989-06-09
Granted
1991-03-19
Kind
A