Katy Perry - Making of the Birthday (Music Video) EXCLUSIVE! - YouTube
Katy Perry Clowns Around Undercover in Brand New 'Birthday' Music Video – Watch Now! | Katy Perry | Just Jared Jr.
Katy Perry's 'Birthday' Video: Katy's The Mistress of Disguise – Billboard
Katy Perry Unveils Official Character Posters For 'Birthday' Music Video - Capital
Katy Perry Tries Character Comedy for Her 'Birthday' Video
Katy Perry - 'Birthday' music video. | Coup De Main Magazine
Katy Perry - Birthday (Official) - YouTube
Katy Perry Birthday music video teaser: Singer is completely unrecognisable as she rocks a series of bizarre costumes in new music video teaser - Mirror Online
Katy Perry - Birthday by HollisterCo on DeviantArt