2.1.231 Part 1 Section 17.7.4.3, basedOn (Parent Style ID)
For additional notes that apply to this portion of the standard, please see the notes for numStyleLink, §17.9.22(a) .
a. The standard allows loops in the style based-on chain.
Word requires that the style based-on chain does not have a circular reference.
b. The standard does not limit the length of the value of the val attribute.
Word restricts the value of this attribute to be at most 253 characters.