in an <b>xsl:for-each</b> or <b>xsl:apply-templates</b>
or <b>saxon:group</b> element to indicate the order in which the selected elements are processed.</p>

<p>The <b>select</b> attribute (default value ".") is a string expression that calculates the sort
key.</p>

<p>The <b>order</b> attribute (values "ascending" or "descending", default "ascending") determines
the sort order. There is no control over language, collating sequence, or data type.</p>

<p>The <b>data-type</b> attribute (values "tex