@Test public void bug57642() throws IOException {
  XSSFWorkbook wb=new XSSFWorkbook();
  XSSFSheet s=wb.createSheet("TestSheet");
  XSSFCell c=s.createRow(0).createCell(0);
  c.setCellFormula("ISERROR(TestSheet!A1)");
  c=s.createRow(1).createCell(1);
  c.setCellFormula("ISERROR(B2)");
  wb.setSheetName(0,"CSN");
  c=s.getRow(0).getCell(0);
  assertEquals("ISERROR(CSN!A1)",c.getCellFormula());
  c=s.getRow(1).getCell(1);
  assertEquals("ISERROR(B2)",c.getCellFormula());
  wb.close();
}