I came across a question https://stackoverflow.com/questions/4114745/resources-on-learning-to-develop-android-apps which is closed as a duplicate of https://stackoverflow.com/questions/1114287/good-book-for-beginning-android-development and https://stackoverflow.com/questions/3350447/the-best-book-for-programming-in-android. Both of these questions are deleted. In this case, how the future visitors will be benefited by the "Possible Duplicates" links?
In such case just flag that question, select other flagging reason and describe it there. Moderator will handle it properly. Moderator either un-delete the duplicate question (if it is suitable for the site) or re-open the question or delete the current question (if it is also not suitable for the site).