2.1.389 Part 1 Section 17.15.1.11, bookFoldPrinting (Book Fold Printing)

a.   The standard says book fold printing divides the page in half vertically with two left margins emanating from the bisector of the page, and two right margins instantiated at the left and right side of the page.

Word divides the page in half vertically with two right margins emanating from the bisector of the page, and two left margins instantiated at the left and right side of the page.