* @return
	 * @see addArrayFormula
	 */
	public Object getArrayFormulaParent( int[] rc )
	{
		Iterator<String> i = arrFormulaLocs.keySet().iterator();
		while( i.hasNext() )
		{
			String addr = i.next();
			int[] arrayRC = ExcelTools.getRangeRowCol( arrFormulaLocs.get( addr ) );
			if( (rc[1] >= arrayRC[1]) && (rc[1] <= arrayRC[3]) &&
					(rc[0] >= arrayRC[0]) && (rc[0] <= arrayRC[2]) )
			{
				return arrayRC;
			}
		}
		return null; // no parent?
	}