code: protected void attachExpansionRuleCitation(Statement statement) {
          AnnotationGroup ag = new AnnotationGroup();
          Citation citation = getInstance().createCitation(getName());
          citation.setType(CitationType.OTHER);
          citation.setReference(getName());
          ag.setCitation(citation);
          statement.setAnnotationGroup(ag);
      }
docs: Attach citation for expansion rule
  
  @param statement {@link Statement}