If U Seek Amy
"If U Seek Amy" was performed at The Circus Starring Britney Spears ( 2009 ) and the Femme Fatale Tour ( 2011 ) . 
<triplet> The Circus Starring Britney Spears <subj> Femme Fatale Tour <obj> followed by <triplet> Femme Fatale Tour <subj> The Circus Starring Britney Spears <obj> follows