teElement('tbody');
    let previousId;
    let previousCell;
    let dupCount = 0;
    this.$headerRefId.textContent = '#' + entry.id;
    this.$headerRefId.setAttribute('href', makeLinkToId(entry.id));
    this.$headerRefId.style.display = 'inline';
    (entry.referencingIds || [])
      .map(id => {
        let cid = menu.search.biblio.refParentClause[id];
        let clause = menu.search.biblio.byId[cid];
        if (clause == null) {
          throw new Error('could not find clause for id ' + cid);
   