text: public override String ToFormulaString(){StringBuilder sb = new StringBuilder();bool needsExclamation = false;if (externalWorkbookNumber >= 0){sb.Append('[');sb.Append(externalWorkbookNumber);sb.Append(']');needsExclamation = true;}if (sheetName != null){SheetNameFormatter.AppendFormat(sb, sheetName);needsExclamation = true;}if (needsExclamation){sb.Append('!');}sb.Append(nameName);return sb.ToString();}