To keep the surface of a book smooth while storing a thick object, and also reduce the weight of the book so that its handling is easy and its transport cost is reduced.

This book consists of a front paper (1), a back paper (2) and a content page paper (4). In addition, the book is equipped with a mount (5) having a recessed part (7) open upward at an appropriate spot. The recessed part (7) is deep enough to match the thickness of the object (6) to be stored. The other part of the mount (5), where the recessed part (7) is not present, has a space (8) including the closed upper surface and likewise the closed bottom surface.