"20th Century Boy" is a 1973 song by glam rock band T. Rex and was released as a stand-alone single. It went to number 3 in the United Kingdom, number 1 in Ireland, number 57 in Australia, number 28 in Spain, number 9 in Norway and number 8 in Germany. It was covered by Def Leppard for their ninth studio album Yeah! in 2006.
↑Brackett, Nathan; Hoard, Christian (2004). The New Rolling Stone Album Guide (4th ed.). Simon & Schuster. p. 822. ISBN978-0-7432-0169-8. Bolan (...) started writing manic chant-along glam-rock hits such as "Metal Guru," "20th Century Boy," "Solid Gold Easy Action," and "Children of the Revolution."