Min/Max for XSLT

Obtaining the MIN:
<!-- Create a variable named $minEventDate containing the MIN date -->
<xsl:variable name="minEventDate">
<xsl:for-each select="event">
<xsl:sort select="@date" data-type="text" order="ascending" />
<xsl:if test="position() = 1">
<xsl:value-of select="@date" />
</xsl:if>
</xsl:for-each>
</xsl:variable>

Obtaining the MAX:
<!-- Create a variable named $maxEventDate containing the MAX date -->
<xsl:variable name="maxEventDate">
<xsl:for-each select="event">
<xsl:sort select="@date" data-type="text" order="descending" />
<xsl:if test="position() = 1">
<xsl:value-of select="@date" />
</xsl:if>
</xsl:for-each>
</xsl:variable>