FR840351A
Expired / Lapsed
FR
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Assignee: Marc Edmond Pifre
•
Filing: 1937-12-29
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Granted: 1939-04-25
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Expires: 1957-12-29
Abstract
No abstract record available.
Inventors
- 👤 Marc Edmond Pifre
- 👤 Armand Victor Marcel Glorie
Bibliographic Details
Application Number
—
Jurisdiction
FR
Data Source
google_patents
Last Synchronized
2026-11-03 06:46
CPC Classifications
H; H04; H04R; H04R3/00; H04R3/002
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References Cited (Backward Citations)
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