DOCBOOK-APPS: FO output: author in simpara, entry and term

When I used <author> in some allowed (according to 4.2 DTD) parents I got
errors during rendering to FO with either xsltproc and instant saxon. I have
fixed this adding to my customization layer following sequence:

<xsl:template match="simpara/author">
  <xsl:apply-templates/>
</xsl:template>

<xsl:template match="entry/author">
  <xsl:apply-templates/>
</xsl:template>

<xsl:template match="term/author">
  <xsl:apply-templates/>
</xsl:template>

Did I it correctly ? Is this intentional hole or just ommision ? In case of
HTML rendering there is nothing wrong.

ABX