Split and Grouped chapters
Split chapters have chapter-like features, such as introductions, chapter summaries, and bibliographies but contain sub-chapters with distinct chapter features of their own. Grouped chapters are presented together because of the close relationship of their content with chapter-like features at the level of the grouping.
Split and grouped chapters use a part element to add a new level above the chapters so that they can share common titles, abstracts etc. This also allows for the div[1-7,N] headings to be at the correct levels throughout the content. Split chapters subsections may be split by letters (e.g. 7A, 7B, 7C) or split by a full stop followed by a successive number (e.g. 4.1, 4.2, 4.3).
Both part and chapter elements should be marked up using
the enumerator element and id values as normal and
appropriate.
Grouped chapters may have a ranged enumerator.