Gwen Stefani looked unreal in her latest selfie which she shared on Instagram - so much so, some of her fans thought she was a doll.The No Doubt singer, 51, looked stunning in a selfie from the set of The Voice, and the combination of her long blonde hair and show-stopping dress sparked some of her followers to compare her to a Barbie doll.Gwen was smiling for the camera with a slick of red lipstick and wearing the quirky one-shouldered dress. MORE: Gwen Stefani channels Marilyn Monroe in