def create_new_source
      @source ||= DataModel::Source.create(
          {
              base_url: 'https://wiki.nci.nih.gov/display/cageneindex/The+Cancer+Gene+Index+Gene-Disease+and+Gene-Compound+XML+Documents',
              site_url: 'https://wiki.nci.nih.gov/display/cageneindex',