// Update any formulas on this sheet that point to
// rows which have been moved
int sheetIndex = _workbook.getSheetIndex(this);
short externSheetIndex = _book.checkExternSheet(sheetIndex);
FormulaShifter shifter = FormulaShifter.createForRowShift(externSheetIndex, startRow, endRow, n);
_sheet.updateFormulasAfterCellShift(shifter, externSheetIndex);
int nSheets = _workbook.getNumberOfSheets();
for(int i=0; i<nSheets; i++) {
Sheet otherSheet = _workbook.getSheetAt(i).getSheet();