* above, so there is also a practical justification for the above.
* It can also be shown, that such degradation occurs if the
* triangulation contains vertices which are member of cells with levels
- * differing by more than one level. On such example is the following:
+ * differing by more than one. One such example is the following:
* \begin{verbatim}
* | | | |
* x-----x-----x--x--x--
* | | |
* x-----------x-----x--
* \end{verbatim}
- * It seems that in two space dimensions, the maximu jump in levels between
- * cells sharing a common vertex is two (as in the example above), this is
+ * It seems that in two space dimensions, the maximum jump in levels between
+ * cells sharing a common vertex is two (as in the example above). This is
* not true if more than four cells meet at a vertex. It is not uncommon
* that a coarse (initial) mesh contains vertices at which six or even eight
* cells meet, when small features of the domain have to be resolved even on
*
* It is assumed that the criterion is a value in a certain norm over each
* element, such that the square of the total error is the sum over the
- * squares of the criteria on the cells.
+ * squares of the criteria on the cells. The criteria shall be positive.
*
*
* \subsection{Material and boundary information}