https://www.britannica.com/biography/John-Legend

https://www.smithsonianmag.com/arts-culture/what-makes-john-legend-americas-most-versatile-artist-180967227/

https://www.encyclopedia.com/people/literature-and-arts/music-popular-and-jazz-biographies/john-legend

https://www.wsj.com/articles/how-singer-songwriter-activist-actor-john-legend-found-his-voice-1541513913

https://www.biography.com/people/john-legend-201302

https://www.notablebiographies.com/newsmakers2/2007-Co-Lh/Legend-John.html