 Complete the following phrase:  Back to Basics was released in August 2006. Aguilera described the record, a double album, as a throwback to jazz, blues, and soul music of the 1920s, 1930s, and 1940s that incorporates a modern twist. She was much inspired by works of such classic blues and soul singers as Otis Redding, Millie Jackson, and Nina Simone during the recording sessions. Back to Basics received generally positive reviews from critics, who commented that the retro-oriented production complements Aguileras vocals. It debuted atop the Billboard 200 and has sold 1.7 million copies in the US. At the 