How to refer to a question or answer in MSE to make easy for someone else to read it?
Is it enough to give the date, including hour, or there is an additional number to identify the question?
How to obtain this number if any? Thanks.
Click on the share button on the bottom of every post. (There's one in the question you just posted, there is also a separate one the answer I'm writing right now.)
If you just want the URL to include in a hyperlink, you can "right click" (or "left" if you are a lefty, command-click or whatever if you use a Mac) and copy the link location from the share button.
If you want to include the reference in an off-line document, see this meta question instead.
The share button should be just about
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