I claim the ornamental design for a book, as shown and described.
FIG. 1 is a front, top and right side perspective view of the book, showing my new design;
FIG. 2 is a top plan view thereof, the bottom plan view being a mirror image thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a rear view thereof;
FIG. 6 is a left side view thereof;
FIG. 7 is a perspective view thereof, shown in an open configuration; and,
FIG. 8 is a perspective view thereof, shown in a folded configuration.
The broken lines in the figures depict environmental subject matter and do not constitute a part of the claimed design.
The pattern sporadically depicted throughout the views is intended to indicate that the pattern is continuous throughout the surface on which the pattern is shown.