About how many months did the Albanian refugees stay in Montenegro before they were forced to return to Kosovo Vilayet?
return the  Albanian refugees stay in  Montenegro ;return the  Albanian refugees were forced to return to  Kosovo Vilayet ;return months of #1 ;return month of #2 ;return the  lowest of #3 ;return the  difference of #4 and  #5
['select', 'select', 'project', 'project', 'aggregate', 'arithmetic']