@Override
 public String getIsbn() {
   String isbn = getPrintIsbn();
   if (!MetadataUtil.isIsbn(isbn)) {
     isbn = getEisbn();
     if (!MetadataUtil.isIssn(isbn)) {
       isbn = null;
     }
   }
   return isbn;
 }
 /**
  * Creates an instance from the current query result set record.
  *
  * @param resultSet the query result set
  * @throws SQLException if any problem occurred accessing the database.
  */
 public BibliographicDatabaseItem(ResultSet resultSet) throws SQLException {
   publisher = resultSet.getString(1);
   seriesTitle = resultSet.getString(2);
   proprietarySeriesIds = new String[1];
   proprietarySeriesIds[0] = resultSet.getString(3);
   publicationTitle = resultSet.getString(4);
   proprietaryIds = new String[1];
   proprietaryIds[0] = resultSet.getString(5);
   eissn = MetadataUtil.formatIssn(resultSet.getString(6));
   printissn = MetadataUtil.formatIssn(resultSet.getString(7));
   eisbn = MetadataUtil.formatIsbn(resultSet.getString(8));
   printisbn = MetadataUtil.formatIsbn(resultSet.getString(9));
   year = resultSet.getString(10);
   volume = resultSet.getString(11);
   coverageDepth = resultSet.getString(12);
   publicationType = resultSet.getString(13);
   provider = resultSet.getString(14);
 }