Patent classification systems

From Inventing aviation
Revision as of 22:47, 8 January 2019 by Econterms (talk | contribs) (explicate)
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There have been many patent classification systems, and any that helpfully classify aero patents in our period are relevant to include here.

Enclosing categories Techtype
Subcategories CPC, IPC, IPC1-7, French patent classifications, USPC, German patent classifications, Canadian patent classifications, NBER patent classification, Belgian patent classifications
Keywords
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