Property of the ScriptLine : BookFormat.
This property is used to determine if a diary is read from front-to-back (the Western way)
or back-to-front (as is done for Arabic and Hebrew books).
Note that this setting does not invert the sequence of DayValues within each page of a GridTemplate. This setting reverses the order of appearance of 2-page layouts (hence preserving the symmetry of left and right pages) but if you wish the dates within these pages to be reversed you must change the placement of tokens so that, for example, DayValues at the top left are 7, and those at the bottom right are 1.