Britney Spears' "If U Seek Amy" pun was cribbed from Joyce and Shakespeare.
Britney: “If U Seek Amy” = “F. U. C. K. me”
Memphis Slim, Stevie Moore, April Wine, Poster Children, The Script: “If You See Kay” = “F. U. C. K.”
James Joyce: “If you see kay / Tell him he may / See you in tea / Tell him from me.” = “F. U. C. K. / x / C. U. N. T. / x”
Shakespeare: “By my life this is my lady’s hand. These be her very C’s, her U’s and her T’s and thus makes she her great P’s.” = “C. U. (N.) T. and thus makes she her great pees.”