How do I retreive missed journal peices?

I was wizzing through the game when I realized I had forgotten to go after journal pages---I missed pages 9-16. Do I need them to finish the game, and if so, I searched the menus and can't see how I can go back to get them. I certainly hope I don't have to restart, but if I do please tell me now!!

Thanx!

Goldendog, you do not need the pages to finish the game. Nor, once you've gone past a segment, can you return to retrieve them. Happy Gaming.