docs: @Override
  	public Response registIssue(String CorpNum, Statement statement, String memo, 
  			String UserID) throws PopbillException {
  			
  		statement.setMemo(memo);
  		
  		String PostData = toJsonString(statement);
  		
  		return httppost("/Statement",
  				CorpNum, PostData, UserID, "ISSUE", Response.class);
  	}