As mentioned [here][1] the commentary attributed to [Rashi][2] on [Avot][3] may not have been authored by him. This is stated by [R. Yaakov Emden][4] in the introduction to "Ets Avot". Which other sources state that the commentary was not authored by him? [1]: https://judaism.stackexchange.com/questions/15520/which-masechtot-dont-really-have-rashi/15574#15574 [2]: https://en.wikipedia.org/wiki/Rashi [3]: https://en.wikipedia.org/wiki/Pirkei_Avot [4]: https://en.wikipedia.org/wiki/Jacob_Emden