[support] Adding other content types to a Book?

[Cozzi]

>From one of the Drupal text books I've learned the following: "Users who
have the Create Book Pages permission, all content nodes will have a new
Outline tab, which they can use to add that node to a book outline."

This sounds very powerful, but I can figure out where it is I am suppose to
see this "Outline"

I believe I Create Book Pages permission, because I've created a Book and
pages within it.

But, when I edit other content types, like Poll, I don't see any indication
of an "Outline" tab.

Best
Cozzi