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• CommentRowNumber1.
• CommentAuthorUrs
• CommentTimeMar 10th 2015

gave the statement that derivations of smooth functions are vector fields a dedicated entry of its own, in order to be able to convieniently point to it

• CommentRowNumber2.
• CommentAuthorTodd_Trimble
• CommentTimeMar 10th 2015
• (edited Mar 10th 2015)

Taking after this style of entry, I decided to write epimorphisms of groups are surjective. Added a little on splittings of exact sequences to split idempotent, and to derivation (mentioning the notion of a derivation of a group valued in a module over that group, a la group cohomology, as a special case of derivations valued in bimodules).

• CommentRowNumber3.
• CommentAuthorUrs
• CommentTimeJul 5th 2017

I have expanded the Idea-section and typed up a detailed proof at derivations of smooth functions are vector fields.

• CommentRowNumber4.
• CommentAuthorUrs
• CommentTimeApr 4th 2021

added pointer to the reference that Dmitri kindly provided over at tangent bundle:

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