function doEndnotes($id)
{
if (!isset($this->endnotes[$id]) || !count($this->endnotes[$id])) {
return '';
}
$e = '<div class="endnotes">';
$e .= '<hr />';
$e .= '<h3>' . __('Notes', 'pressbooks') . '</h3>';
$e .= '<ol>';
foreach ($this->endnotes[$id] as $endnote) {
$e .= "<li><span>{$endnote}</span></li>";
}
$e .= '</ol></div>';
return $e;
}