Super Smash Bros. + Wii U GameCube Controller Adaptor Wii U | Zavvi France
Wii U Pro Controller - Wikipedia
Super Smash Bros.' for Wii U is completely insane and absolutely amazing | The Verge
Nintendo of America on Twitter: "Get excited! The #WiiU version of # SmashBros. will be playable with GameCube controllers. http://t.co/nmyj9QMsuU" / Twitter
Wii U's GameCube controller will support more than just Smash Bros. [updated] | VentureBeat