Take a tea towel and stretch it over a thin paste board or poster board that is larger than your page. Tape it to the back board outside of the margins of the page. Get the front flat.
Heat the iron to a steam setting, I use the same temp that I would for cotton.
Start at the last wrinkled page in the book. Slip in the board behind the wrinkled page and gently iron it flat.
Repeat to the front of the wrinkled pages.
That is what I found on some forums. I have never encountered this
problem myself. But this woman has some experience with it, in fact,
her pages were wrinkled because water was spilled on it. So this might
do the trick for you. ^-^
That is what I found on some forums. I have never encountered this 
