View source for DE 77f

From the Swedish patent's office's "Introduction to the German Patent Classification (DPK)" online:<ref>[https://www.prv.se/en/patents/patent-online-services/the-german-patent-classification-dpk/the-german-patent-classification-dpk-in-english/introduction-to-the-german-patent-classification-dpk/] </ref>
:The German Patent Office started developing a classification system for its patent documents in 1877. It was published in seven editions between 1906 and 1958, first as "Verzeichnis der deutschen Patentklassen" and later as "Gruppeneinteilung der Patentklassen". Between the editions, modifications were published in the form of "Änderungen" and "Ergänzungslieferungen".
The subsets of the German classes are listed in English on the Swedish site [https://www.prv.se/en/patents/patent-online-services/the-german-patent-classification-dpk/the-german-patent-classification-dpk-in-english/ here], and in particular class 77's subsets, linked from that page, are listed [https://www.prv.se/globalassets/dokument/patent/spd/klassystem/dpk/dpken/77.pdf here].
In that context, DE 77f covers the category of "Toys."  We don't know for certain that the meaning of DE 77f was the same at the time early aero.
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{{Standard techtype reports}}
{{Techtype
|Enclosing categories=DE 77
|Subcategories=DE 77f.23
|Keywords=toys
}}