DE681973C
Expired / Lapsed
DE
⏱️ 0.0 years remaining
Textbook with interchangeable sheets
Assignee: Individual
•
Filing: 1938-08-28
•
Granted: 1939-10-05
•
Expires: 1958-08-28
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-10-28 02:41
CPC Classifications
G; G09; G09B; G09B3/00; G09B3/02; G09B3/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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