User talk:2A01:4C8:475:5899:A028:230C:4154:1C74

May 2021
Please refrain from making unconstructive edits to Wikipedia, as you did at Doppler effect. Your edits appear to constitute vandalism and have been reverted. If you would like to experiment, please use the sandbox. Repeated vandalism may result in the loss of editing privileges. Thank you. Favonian (talk) 21:35, 6 May 2021 (UTC)