return me the author in the " University of Michigan " whose papers have more than 5000 total citations . 
return authors ;return #1 in the  University of  Michigan ;return papers of  #2 ;return citations of  #3 ;return the  number of  #4 for each #2 ;return #2 where #5 is  more than 5000
['select', 'filter', 'project', 'project', 'group', 'comparative']