Buz Kohan, the writer of "Little Drummer Boy/Peace On Earth" revealed in an interview with CBS how the duet between David Bowie and Bing Crosby came together. Watch the interview with Kohan, plus watch video of the classic performance which aired on Crosby's 1977 Merry Old Christmas Special:
David Bowie/Bing Crosby "Little Drummer Boy/Peace On Earth"