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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeOct 7th 2009
   • PermaLink
   Author: Urs
   Format: Markdowncreated [[Tietze extension theorem]]

   created Tietze extension theorem

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeOct 25th 2010
   • PermaLink
   Author: Urs
   Format: MarkdownItexI added a brief statement of the continuous version of the [[Tietze extension theorem]], but it's just a stub then I tried to polish the remark about the smooth version. My earlier version wasn't very good. I hope now it's a bit better.

   I added a brief statement of the continuous version of the Tietze extension theorem, but it’s just a stub

   then I tried to polish the remark about the smooth version. My earlier version wasn’t very good. I hope now it’s a bit better.

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeJul 5th 2017
   • PermaLink
   Author: Urs
   Format: MarkdownItexI have spelled out a proof of the Tietze extension theorem for continuous functions, [here](https://ncatlab.org/nlab/show/Tietze+extension+theorem#ForContinuousFunctions)

   I have spelled out a proof of the Tietze extension theorem for continuous functions, here

4. • CommentRowNumber4.
   • CommentAuthorDavidRoberts
   • CommentTimeSep 25th 2019
   • PermaLink
   Author: DavidRoberts
   Format: MarkdownItexAdded [[Taimanov theorem]] as related entry <a href="https://ncatlab.org/nlab/revision/diff/Tietze+extension+theorem/28">diff</a>, <a href="https://ncatlab.org/nlab/revision/Tietze+extension+theorem/28">v28</a>, <a href="https://ncatlab.org/nlab/show/Tietze+extension+theorem">current</a>

   Added Taimanov theorem as related entry

   diff, v28, current

5. • CommentRowNumber5.
   • CommentAuthorUrs
   • CommentTimeJun 30th 2022
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded pointer to the original * [[Heinrich Tietze]], *Über Funktionen, die auf einer abgeschlossenen Menge stetig sind*, Journal f&uuml;r die reine und angewandte Mathematik, **145** (1915) &lbrack;[doi:10.1515/crll.1915.145.9](https://doi.org/10.1515/crll.1915.145.9)&rbrack; and to this early generalization (to codomains which may be locally convex topological vector spaces): * [[James Dugundji]], *An extension of Tietze's theorem*, Pacific Journal of Mathematics **1** 3 (1951) &lbrack;[doi:10.2140/pjm.1951.1.353](http://dx.doi.org/10.2140/pjm.1951.1.353), [pdf](https://msp.org/pjm/1951/1-3/pjm-v1-n3-p04-p.pdf)&rbrack; <a href="https://ncatlab.org/nlab/revision/diff/Tietze+extension+theorem/31">diff</a>, <a href="https://ncatlab.org/nlab/revision/Tietze+extension+theorem/31">v31</a>, <a href="https://ncatlab.org/nlab/show/Tietze+extension+theorem">current</a>

   added pointer to the original

   • Heinrich Tietze, Über Funktionen, die auf einer abgeschlossenen Menge stetig sind, Journal für die reine und angewandte Mathematik, 145 (1915) [doi:10.1515/crll.1915.145.9]

   and to this early generalization (to codomains which may be locally convex topological vector spaces):

   • James Dugundji, An extension of Tietze’s theorem, Pacific Journal of Mathematics 1 3 (1951) [doi:10.2140/pjm.1951.1.353, pdf]

   diff, v31, current