Due to [CC-BY-SA 3.0][1] license on SE network, once a post is published to the SE network, then it's released to the community.  Therefore, *everyone has the right to use the contents of every post provided that the post owner is properly attributed* (through a URL).

The self-deletion action *doesn't* nullify the act of posting, so in principle, the previous paragraph applies to self-deleted posts as well.  In practice, 10k users can view *all* deleted posts by their URL, so it won't be difficult to click "edit" to retrieve the Markdown source code of the self-deleted post and repost.

For other users, they may *put the URL of the self-deleted question*, which is viewable by 10k users, in order to properly attribute the original answerer.  They may omit the original question asker's user name and the original question title since it's *covered* by a message like "this question has been deleted"---the URL will enable 10k users to find out the original question.  Nevertheless, the re-posted question should be *complete* in the sense that it's *answerable on its own*.

  [1]: https://creativecommons.org/licenses/by-sa/3.0/