Cells cells = workbook.getWorksheets().get(0).getCells();
Cell cell = cells.get("A12");
//Tracing precedents of the cell A12.
//The return array contains ranges and cells.
ReferredAreaCollection ret = cell.getPrecedents();
//Printing all the precedent cells' name.
if(ret != null)
{
for(int m = 0 ; m < ret.getCount(); m++)
{
ReferredArea area = ret.get(m);
StringBuilder stringBuilder = new StringBuilder();
if (area.isExternalLink())
{
stringBuilder.append("[");
stringBuilder.append(area.getExternalFileName());