Fortunately, these were made one summer when Wil was visiting me in the US so I know how they were made.
We started with regular 3 ring binders and sawed off most of the cover and back except for the bit that covers the binder rings and the spine. To that was connected sheets of plexiglass cut to size.
It makes a great coffee table book (which is where Wil displays hers) so that one can always see the quilts. Here are two of her books. I believe she is beginning to fill book #4
To insert the quilts into the book, she stitches O-rings onto the backs of the quilts.