Question: Ivory Tower was recorded as an R&B version by which baritone singer?

Context paragraphs:
Atgof o'r Sêr: Atgof o'r Sêr (English: "Memory of the Stars" ) is a musical composition by Welsh contemporary composer Robat Arwyn.  It was commissioned for the 2001 National Eisteddfod of Wales in Denbighshire and was written specifically for baritone singer Bryn Terfel, soprano Fflur Wyn, and the Ruthun and District Choir.

Ivory Tower (1956 song): "Ivory Tower" is a popular song written by Jack Fulton and Lois Steele.  Popular versions by Cathy Carr and Gale Storm, and a rhythm & blues version by Otis Williams all received major popularity in 1956.  Carr's version reached #2 and Storm's #6 on the Billboard pop charts, while Williams' version reached #11 on Billboard's R&B chart.  Carr's version achieved #2 on the Australian charts.

The Ivory Tower (album): The Ivory Tower is the debut album of Californian rock band Takota.  The album was released on May 16, 2006 on Ares Records and was produced by Atreyu singer/drummer Brandon Saller.

Levi Stubbs: Levi Stubbs (born Levi Stubbles, June 6, 1936 – October 17, 2008) was an American baritone singer, best known as the lead vocalist of the R&B group the Four Tops, a group known for a variety of Motown hit records and other songs created in the 1960s and 1970s.  He has been noted by writers for his emotional, often dramatic, style of singing.

Deane Waretini, Snr.: Deane Waretini, Snr.  was a famous Maori baritone singer from Rotorua.  He was possibly the first Maori singer to be commercially recorded.  His son Deane Waretini would also be a first with his no 1 hit The Bridge, which became the first Maori language song to be no 1 in the New Zealand music charts.

Anna Abreu (album): Anna Abreu is the self-titled debut album by Finnish singer and season three "Idols" runner-up Anna Abreu, released in Finland by RCA on August 22, 2007.  "End of Love" was released as the album's lead single, followed by "Ivory Tower", and "Are You Ready" (a cover of the 2005 hit by Australian duo Shakaya).

Otis Williams: Otis Williams (born Otis Miles Jr.; October 30, 1941) is an American baritone singer.  Nicknamed "Big Daddy", he is occasionally also a songwriter and a record producer.  Williams is best known as the founder and last original surviving member of the Motown vocal group The Temptations, a group in which he continues to perform.  He also owns the rights to the Temptations name.

Ivory Tower (Anna Abreu song): "Ivory Tower" is a song by Finnish singer Anna Abreu from her debut studio album, "Anna Abreu" (2007).  Rauli Eskolin (known professionally as Rake) wrote and produced the song along with Teemu Brunila.  It is a Pop song with R&B rhythms.  The song was released on 15 October 2007 in Finland, as the album's second single.

You Know That I Love You (Donell Jones song): "You Know That I Love You" is a song by American recording artist Donell Jones, released on April 9, 2002 as the first single from the album, "Life Goes On" (2002).  Jazz saxophonist Kim Waters covers "You Know That I Love You" on his 2002 album titled "Someone to Love You", and Kim Waters' cover was picked by several Urban AC stations and some stations such as KJLH in Los Angeles played the Donell Jones version with the jazz mixed in late 2002, which started playing the original R&B version on the week of March 25, 2002.  The single received major airplay on Mainstream Urban, CHR/Rhythmic and Urban AC radio stations.  KKBT in Los Angeles started playing it on April 1, 2002 a week after it officially it impacted Urban Radio.

Marvin Gaye Recorded Live on Stage: Marvin Gaye Recorded Live on Stage is the first live album released by singer Marvin Gaye on the Tamla label.  Recorded during a Motortown Revue show at Chicago's Regal Theater, the album showcased the musician performing early hits such as "Stubborn Kind of Fellow", "Pride and Joy" and "Hitch Hike" while also adding in unreleased numbers including "One of These Days" (a studio version was released on the b-side of "Pride And Joy" and later as a track on Gaye's 1966 album, "Moods of Marvin Gaye"), "Mo Jo Hanna" and "That Stubborn Kinda Fellow" album track, "Get My Hands on Some Lovin'" while also singing three covers - the jazz standard, "Days of Wine and Roses", blues song "Mo Jo Hanna" and his cover of Ray Charles' R&B version of "You Are My Sunshine".

Supporting paragraphs: Ivory Tower (1956 song) Otis Williams
Answer: Otis Williams