How to close a book in Apple Books app in iPadOS 17?

In iPadOS 17, I seem to be stuck inside an open book. I cannot find a way to close a book. I want to return to my list of books, and the book store, etc. When I tap in the middle of the screen, I get a small notice at the top telling me my percentage through this open book. And I get a small icon in the lower right corner that when tapped offers font settings. But I cannot find a way to exit the current book.