Procedure ToTiff(p_Printer: PrinterDriver; p_InputFile, p_OutputFile: String);
  var ExcelApp: ExcelApplication;
  var Workbook: ExcelWorkbook;
  var Worksheet: ExcelWorksheet;
  var ReadOnly: OleVariant;
  var Missing: OleVariant;
  var LocaleID: Integer;
  var SaveChanges: OleVariant;
  begin
    // Create a Excel's Application object
    ExcelApp := CoExcelApplication.Create;

    ReadOnly := True;
    Missing := Variants.EmptyParam;

    // Set en-US locale or call GetThreadLocale
    LocaleID := $0409;
    Workbook := ExcelApp.Workbooks.Open(p_InputFile, 2, ReadOnly, Missing, Missing, Missing, Missing, Missing, Missing, Missing, Missing, Missing, Missing, Missing, Missing, LocaleID);

    // Loop through each worksheet
    for Worksheet in Workbook.Worksheets do
    begin
      Writeln(' - Processing worksheet ', Worksheet.Index, ' (', Worksheet.Name, ')');
    end;

    // Close the workbook and exit excel
    SaveChanges := False;
    Workbook.Close(SaveChanges, Missing, Missing, LocaleID);
    ExcelApp.Quit;
  end;