katy perry lady gaga ft. ke$ha

Flip This! (Avicii x The Cataracs x Ellie Goulding x Katy Perry x Flo Rida x Ke$ha x David Guetta x Lady Gaga x Waka Flocka x Rihanna x Birdman x Belinda Carlisle) 

My First 3 Way (Journey vs. 3oh!3 feat. Ke$ha vs. Britney Spears vs. Lady Gaga feat. Beyoncé vs. Katy Perry vs. Taylor Swift vs. 

Cali Girls Need to Dance (Lady Gaga vs. Lady Antebellum vs. Katy Perry vs. Ke$ha)