* operators and the like), but has no functionality to actually
* dereference data. This is done in the derived classes.
*
- * @section TAInternals Internals
+ * <h3>Internals</h3>
*
* There is a representation of past-the-end-pointers, denoted by
* special values of the member variables #present_level and
* these accessors, the structure of these classes is hidden from the
* application program.
*
- * @section TIDiff Which iterator to use when
+ * <h3>Which iterator to use when</h3>
*
* @attention Application programs will rarely use TriaRawIterator,
* but rather one of the derived classes TriaIterator or
* <li> TriaActiveIterator objects which only loop over active cells.
* </ul>
*
- * @section TIPurpose Purpose
+ * <h3>Purpose</h3>
*
* Iterators are not much slower than operating directly on the data
* structures, since they perform the loops that you had to handcode
* e.g. <em>count_if</em> (see the documentation for Triangulation for
* an example) and several others.
*
- * @section TIImplementation Implementation
+ * <h3>Implementation</h3>
*
* The iterator class itself does not have much functionality. It only
* becomes useful when assigned an Accessor (the second template
* checked and implemented.
*
*
- * @section Past-the-end iterators
+ * <h3>Past-the-end iterators</h3>
*
* There is a representation of past-the-end-pointers, denoted by special
* values of the member variables @p present_level and @p present_index: