question: who has played for manchester city and manchester united and liverpool?
#1 return manchester  city 
#2 return manchester  united 
#3 return liverpool 
#4 return who  played for #1 
#5 return who  played for #2 
#6 return who  played for #3 
#7 return who  is in  both  #4 and #5 
#8 return who  is in  both  #6 and #7