Question: What duet performed Peace on Earth/Little Drummer Boy
Context: A Mary Christmas is the eleventh studio album and first Christmas album by American R&B recording artist Mary J. Blige.  Produced by David Foster, it was released on October 15, 2013 via Matriarch, Interscope and Foster's Verve Records, compromising soulful interpretations of classic holiday tunes such as "Little Drummer Boy", "Do You Hear What I Hear? " and "Have Yourself a Merry Little Christmas". Ultimate Hits: Rock and Roll Never Forgets is a compilation album by American rock singer–songwriter Bob Seger.  The double-disc album was released on November 21, 2011 and contains 26 remastered tracks from throughout Seger's career, which spans more than four decades.  Included are the original mono version of "Ramblin' Gamblin' Man", Seger's first hit with The Bob Seger System from 1968, the classic Christmas song "The Little Drummer Boy" from 1987's "A Very Special Christmas", which makes its first appearance on a Seger album, and previously unreleased cover versions of Tom Waits' "Downtown Train" and Little Richard's "Hey, Hey, Hey, Hey (Going Back to Birmingham)."  There is also a Walmart exclusive edition that includes the bonus track "Living Inside My Heart," a song from the soundtrack of the 1986 film "About Last Night...", which has also never before been released on any Bob Seger album.  Two songs on this compilation album are edited compared to the original releases: "We've Got Tonight" is the single edit, which is about one minute shorter than the album version, and "Katmandu" is a newly edited version which omits the second verse, making the song also about one minute shorter compared to the original album version.  In the US it was certified gold and platinum in June 2013 by the RIAA. White Christmas and Little Drummer Boy Live is a limited edition, 4-piece vinyl-only release by Mark Kozelek.  It is a compilation of two previously released limited edition live CD releases, "White Christmas Live" (2001) and "Little Drummer Boy Live" (2006).  The fourth record features an exclusive bonus track, an alternate recording of "Have You Forgotten." "Peace on Earth/Little Drummer Boy" (sometimes titled "The Little Drummer Boy/Peace on Earth") is a Christmas song with an added counterpoint performed by David Bowie and Bing Crosby. " The Little Drummer Boy" is a Christmas song written in 1941, while the "Peace on Earth" tune and lyrics, written by Ian Fraser, Larry Grossman, and Alan Kohan, were added to the song specially for Bowie and Crosby's recording. ReJoyce: The Christmas Album is the fourth studio album by American pop singer Jessica Simpson.  It was released by Columbia Records on November 23, 2004.  The album features cover versions of popular Christmas songs and includes a duet with her sister, Ashlee Simpson, on the song "Little Drummer Boy".  Additionally, it also includes a duet with Nick Lachey, Simpson's husband at the time, on "Baby, It's Cold Outside".  The cover of Amy Grant's "Breath of Heaven (Mary's Song)" was notable, as Simpson has said that Amy Grant is one of her favorite recording artists and her role model. Rare (often known as Bowie Rare) was a compilation released by RCA Records to cash in on David Bowie for the 1982 Christmas market.  The artist's relations with the company were at a low – Bowie had recorded his last music for RCA with the "Baal EP", and had been annoyed by the release of a five-year-old duet with Bing Crosby ("Peace on Earth/Little Drummer Boy") as a single without his consultation.  Bowie let it be known he was unhappy with the "Rare" package, and would sign with EMI for his next album.  All of the songs were being issued for the first time on an LP and cassette. Bing Crosby's Merrie Olde Christmas is a posthumous 1977 Christmas television special starring Bing Crosby and his family with special guests Twiggy, David Bowie, Ron Moody, Stanley Baxter and Trinity Boys Choir.  It was Crosby's final Christmas special, recorded just five weeks before his death on October 14, 1977, and is also known most notably for its musical highlight of the iconic duet by the unusual pairing of Crosby and Bowie on "Peace on Earth/Little Drummer Boy", Drummer Boy is an EP release by Christian folk group Jars of Clay featuring a new interpretation of the classic 1958 Christmas Carol "Little Drummer Boy".  The EP was originally released by Essential Records in the Christmas following the release of "Jars Of Clay" in 1995.  The EP was re-released as a two-pack with "Jars of Clay" prior to their second album, "Much Afraid". "6 Years of Boney M. Hits (Boney M. on 45)" is a greatest hits medley by Boney M., inspired by the success of the hit medleys by Stars on 45.  Originally released on the B-side of the band's 1981 Christmas single "Little Drummer Boy", the single was flipped over in January 1982 with the medley as an A-side.  While failing to chart in Germany, the medley reached #6 in the Spanish charts and was also an A-side release in France and Japan.  The 12" version featured a faded version on the German pressing and an unfaded version on the French pressing, while the UK version (included on the B-side of their UK top 40 hit "We Kill the World") was extended with their Christmas chart-topper "Mary's Boy Child - Oh My Lord". One Wish: The Holiday Album is the sixth studio album by American singer Whitney Houston, released in November 2003.  The album is a Christmas album, and featured the single "One Wish (for Christmas)", which reached the top twenty on "Billboard"' s US Adult Contemporary chart.  The album spent six weeks on the "Billboard" 200 and as of January 2013 it had sold over 546,000 copies to date.  The album also features a duet with Houston's daughter Bobbi Kristina on "The Little Drummer Boy".  The album also re-uses "Joy to the World" and "Who Would Imagine a King" from 1996's "".
Answer: Crosby and Bowie