I love this arrangement! I love these voices! I love this time of year!
The Little Drummer Boy was written in 1957 by Katherine K. Davis while Peace on Earth was written in 1977 by Larry Grossman, Ian Fraser and Buz Kohan especially for David Bowie to sing in counterpoint for this performance because he didn't like The Little Boy. Bing died a month after recording this 1977 television special, "Bing Crosby's Merrie Olde Christmas."
The Little Drummer Boy/Peace on Earth by Bing Crosby and David Bowie
Wikipedia about this song/performance