American singer Gwen Stefani has recorded material for four studio albums and one extended play (EP), and has been featured on songs on other artists' respective albums. After releasing five studio albums with ska punk group No Doubt, in 2004 Stefani began work as a solo artist, developing her pop debut Love. Angel. Music. Baby. in the same year. It produced several top ten singles worldwide, including "What You Waiting For?", "Rich Girl", and "Hollaback Girl", the latter of which was the first single to sell over a million digital copies in the United States. The record contained work from a variety of producers and songwriters, including Linda Perry, Nellee Hooper, André 3000, and No Doubt bandmate Tony Kanal. "Cool", "Luxurious", and "Crash" were also released as the singles. In 2005, S