What are the names of the stations which serve both "Ananthapuri Express" and "Guruvayur Express" trains?
return stations ;return trains #1 serve ;return #1 where #2 is  Ananthapuri Express  ;return #1 where #2 is  Guruvayur Express  ;return #1 of  both #3 and  #4 ;return names of  #5
['select', 'project', 'comparative', 'comparative', 'intersection', 'project']