Question: Fonzi Thornton has provided vocal accompaniment for which guitarist known for the song "Poetry Man"?
Context: Pilgrimage is a 2001 documentary film by Werner Herzog.  Accompanied only by music the film alternates between shots of pilgrims near the tomb of Saint Sergei in Sergiyev Posad, Russia and pilgrims at the Basilica of Guadalupe in Mexico.  The score was composed by John Tavener and performed by the BBC Symphony Orchestra with vocal accompaniment by Parvin Cox and the Westminster Cathedral Choir.  The film begins with a supposed quote by Thomas à Kempis, invented by Herzog. Phoebe Snow (born Phoebe Ann Laub; July 17, 1950 – April 26, 2011) was an American singer, songwriter, and guitarist, best known for her 1975 song "Poetry Man".  She was described by "The New York Times" as a "contralto grounded in a bluesy growl and capable of sweeping over four octaves." Naka Rabemanantsoa is a pianist and composer of "vakondrazana" and "ba-gasy" music from the central highlands of Madagascar.  He was a major composer for the Malagasy theatrical genre that reached its peak between 1920 and 1940 at the Theatre d'Isotry in Antananarivo.  His pieces were typically written for piano, and although his pieces were often adapted for solo, duet or choral vocal accompaniment sung in the Malagasy language, he was a strong proponent of preserving strictly instrumental accompaniment for theatrical performances.  His songs form part of the canon of classical Malagasy piano music, and a street in downtown Antananarivo is named after him. "I Luh Ya Papi" is a song recorded by American singer Jennifer Lopez for her eighth studio album, "A.K.A." (2014).  Featuring guest vocals from American rapper French Montana, the song was released on March 11, 2014 as the lead single from the album by Capitol Records.  The song was written and produced by Noel "Detail" Fisher, with additional writing from Andre Proctor, Karim Kharbouch, and Lopez.  Cory Rooney and Fisher provided vocal production for the song.  Musically, "I Luh Ya Papi" is hip hop song, backed with synths and metallic beats, that lyrically contains innuendoes and references to Lopez's body. "Heaven of My Life" is a 1981 album cut by Change from the LP "Miracles", which featured vocals by Diva Gray, Jocelyn Shaw, Tanyayette Willoughby and James Robinson on leads, and Luther Vandross, Crystal Davis, Ullanda McCullough, Benny Diggs, Dennis Collins and Fonzi Thornton providing the backups.  The song also featured a unique guitar breakdown performed by Doc Powell.  Along with "Paradise" and "Hold Tight", it became a number one single on the US dance chart for five weeks.  It was released as a promotional single in October 1981. "So Fine" is a 1982 soul/dance single by Howard Johnson, former lead singer of Niteflyte.  The single made it to number one on the dance charts for one week.  "So Fine" peaked at number six on the soul singles chart, but failed to make the Hot 100.  Fonzi Thornton provided vocals on the single.  "So Fine" was sampled by DJ Quik on his song "Down, Down, Down" on the album "Rhythm-al-ism".  It was also sampled by MED on his song "MEDical Card". "Girls" is a song recorded by American singer Jennifer Lopez for her eighth studio album, "A.K.A." (2014).  It features a guest rap from American rapper Tyga.  The song was written and produced by the song's producer Dijon "DJ Mustard" McFarlane, with additional writing from Asia Bryant, and Lopez.  Cory Rooney, Trevor Muzzy, and Bryant provided vocal production for the song.  A solo version of "Girls" was released on January 27, 2014, as the first promotional single from "A.K.A.". Accompaniment is the musical parts which provide the rhythmic and/or harmonic support for the melody or main themes of a song or instrumental piece.  There are many different styles and types of accompaniment in different genres and styles of music.  In homophonic music, the main accompaniment approach used in popular music, a clear vocal melody is supported by subordinate chords.  In popular music and traditional music, the accompaniment parts typically provide the "beat" for the music and outline the chord progression of the song or instrumental piece.  The accompaniment for a vocal melody or instrumental solo can be played by a single musician playing an instrument such as piano, pipe organ, or guitar.  While any instrument can in theory be used as an accompaniment instrument, keyboard and guitar-family instruments tend to be used if there is only a single instrument, as these instruments can play chords and basslines simultaneously (chords and a bassline are easier to play simultaneously on keyboard instruments, but a fingerpicking guitarist can play chords and a bassline simultaneously on guitar).  A solo singer can accompany herself by playing guitar or piano while she sings, and in some rare cases, a solo singer can even accompany himself or herself just using his or her voice and body (e.g., Bobby McFerrin). Alfonso "Fonzi" Thornton is an American singer, songwriter/producer and vocal contractor.  In a career spanning 40 years, Thornton has sung backing vocals for top artists across many genres of music.  His vocal credits can be found on the recordings of Aretha Franklin, Luther Vandross, Bryan Ferry, Roxy Music, CHIC, Diana Ross, Garth Brooks, Ray Charles, Mariah Carey, David Bowie, Robert Palmer, Patti Labelle, Al Jarreau, Celine Dion, Phoebe Snow and Bette Midler and many others.  In 2008, Thornton joined the musical entourage of the Queen of Soul, Aretha Franklin as backing vocalist and vocal contractor and continues to accompany her in concert, on recordings and TV. Everything Stops for Tea is an album by John Baldry released in May 1972.  It was produced by Elton John and Rod Stewart.  Elton provides vocal accompaniment on tracks 1, 3-5.  Stewart provides vocal accompaniment and plays banjo on track 8.
Answer: Phoebe Snow