There is a notice added to my answer that says:
This post does not cite any references or sources ...
But it does not say how to react on this. So I added sources now, but how do I inform the reviewer about my measurements?
You can notify a moderator by flagging the answer. If there was an automated alert, it would probably come in the form of a flag by the Community user. For now, manual flagging is probably the best way to ask to have the notice removed.
There is a page on UX.SE where you can view those questions / answers with notifications against them:
Each post that has had a notification left against it that has since changed should therefore float to the top of this list, so it may be the case that this page is one that needs to be monitored by us Mods.
/Edit - having spoken with the skeptics.stackexchange mods (where these notifications originated) they confirm that there is no set way for the moderators to be alerted. They rely on the user flagging their question for moderator attention.
One point of note is that they say that it rarely happens over on skeptics anyway; while lots of the notifications are added very few are actually acted upon. I take it as a good thing that we have to have this discussion here on meta.UX about how to handle improved answers.