code: def _get_pubs(self, entry, graph):
          
  
          ref_to_pmid = {}
          entry_num = entry['mimNumber']
          if 'referenceList' in entry:
              reflist = entry['referenceList']
              for rlst in reflist:
                  if 'pubmedID' in rlst['reference']:
                      pub_id = 'PMID:' + str(rlst['reference']['pubmedID'])
                      ref = Reference(
                          graph, pub_id, self.globaltt['journal article'])
                  else:
                      # make blank node for internal reference
                      pub_id = '_:OMIM' + str(entry_num) + 'ref' + str(
                          rlst['reference']['referenceNumber'])
  
                      ref = Reference(graph, pub_id)
                      title = author_list = source = citation = None
                      if 'title' in rlst['reference']:
                          title = rlst['reference']['title']
                          ref.setTitle(title)
                      if 'authors' in rlst['reference']:
                          author_list = rlst['reference']['authors']
                          ref.setAuthorList(author_list)
                          citation = re.split(r'\.\,', author_list)[0] + ' et al'
                      if 'source' in rlst['reference']:
                          source = rlst['reference']['source']
                      citation = '; '.join(
                          [tok for tok in [citation, title, source] if tok is not None])
                      ref.setShortCitation(citation)
                  ref.addRefToGraph()
                  ref_to_pmid[rlst['reference']['referenceNumber']] = pub_id
  
                  # add is_about for the pub
                  omim_id = 'OMIM:' + str(entry_num)
                  graph.addTriple(omim_id, self.globaltt['mentions'], pub_id)
  
          return ref_to_pmid
docs: Extract mentioned publications from the reference list
          :param entry:
          :return: