Groups

Content flows can be grouped together using a <group> statement, for example:

<flows>
  <group name="chapters">
    <chapter-one>
      ...
    </chapter-one>

    <chapter-two>
      ...
    </chapter-two>
  </group>
</flows>

declares a new group named "chapters" which consists of two flows, "chapter-one" and "chapter-two". Groups can even be nested (meaning a group can contain other groups instead of content flows).

For more information on groups and their uses, take a look at page repeats.