Page down/up keyboard shortcut on iPad w/ external keyboard?

I use an Apple Magic Keyboard with my iPad. I’ve been unable to find a shortcut combination that works to page up/down.

When not in edit mode, I expected that space/shift space might work, as it does on Safari. But that doesn’t seem to be the case.

I have searched, but – so far – no joy.

Anyone else have this issue (or solved it)?