endnotes.heading.command — LaTeX command of the endnotes headings
      <xsl:param name="endnotes.heading.command"/>
With this parameter you can provide your own latex macro to make the
    endnotes headings. If not set, dblatex uses the default
    sectionning commands like \section*,
    \subsection*, and so on. The command takes one
    parameter that is the title markup of the heading.
    For more details see the section called “Grouping Endnotes”.