Kesha
Artist: Britney Spears
Song: "Till The World Ends" (2011)
Kesha was a pop star in her own right when she passed along this track to
Britney Spears - a decision she stands by even after the song sold over a million copies.
“It really solidifies me as a songwriter in the pop music world, which is what I consider myself first and foremost," she explained.
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