Question:
Henry John Deutschendorf Jr. (December 31, 1943 - October 12, 1997), known professionally as John Denver, was an American singer-songwriter, record producer, actor, activist, and humanitarian, whose greatest commercial success was as a solo singer. After traveling and living in numerous locations while growing up in his military family, Denver began his music career with folk music groups during the late 1960s. Starting in the 1970s, he was one of the most popular acoustic artists of the decade and one of its best-selling artists. By 1974, he was firmly established as one of America's best-selling performers, and AllMusic has described Denver as "among the most beloved entertainers of his era".
Denver began his recording career with a group that had started as the Chad Mitchell Trio; his distinctive voice can be heard where he sings solo on Violets of Dawn, among other songs. He recorded three albums with the Mitchell Trio, replacing Chad Mitchell himself as high tenor. The group Denver, Boise, and Johnson, which had evolved from the Mitchell Trio, released a single before he moved on to a solo career. Bill Danoff and Taffy Nivert, credited as co-writers of Denver's song "Take Me Home, Country Roads", were close friends of Denver and his family, appearing as singers and songwriters on many of Denver's albums until they formed the Starland Vocal Band in 1976. The band's albums were released on Denver's Windsong Records (later known as Windstar Records) label. Denver's solo recording contract resulted in part from the recording by Peter, Paul, and Mary of his song "Leaving on a Jet Plane", which became the sole number-1 hit single for the group. Denver recorded songs by Tom Paxton, Eric Andersen, John Prine, David Mallett, and many others in the folk scene. His record company, Windstar, is still an active record label today. Country singer John Berry considers Denver the greatest influence on his own music and has recorded Denver's hit "Annie's Song" with the original arrangement. Olivia Newton-John, an Australian singer whose across-the-board appeal to pop, MOR, and country audiences in the mid-1970s was similar to Denver's, lent her distinctive backup vocals to Denver's 1975 single "Fly Away"; she performed the song with Denver on his 1975 Rocky Mountain Christmas special. She also covered his "Take Me Home, Country Roads", and had a hit in the United Kingdom (#15 in 1973) and Japan (#6 in a belated 1976 release) with it. In 1976, Denver appeared as a guest star, along with Olivia Newton-John, who made a cameo appearance, on The Carpenters Very First Special, a one-hour TV special broadcast on the ABC television network. A highlight of the program was John singing a duet with Karen Carpenter of a medley of "Comin' Thro' the Rye" and "Good Vibrations", although the medley was never released commercially as a single or on an album.
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what other artists did his record company work with

Answer:
Tom Paxton, Eric Andersen, John Prine, David Mallett, and many others in the folk scene.

input: During the recording of the group's first studio album Exposure, the personnel of the group changed. Reports vary based on the source. According to People magazine, one of the original singers quit while two of the girls were fired midway through the recording of the first album, but according to Billboard, all three were fired. Arista records felt that the three original singers lacked star potential. Martinee states that he made the decision himself to replace the three girls, while Miller maintains it was all their choice, and Jurado confirms that Lorenzo wanted to leave. Shortly thereafter, Casanas pursued a solo career and Lorenzo pursued other ambitions; they were replaced by Jeanette Jurado and Gioia Bruno. Miller began a solo career; she was replaced by Ann Curless. Lorenzo returned to the dance charts with the Vendetta Records releases "I Wanna Know" in 1988, and "Stop Me if I Fall in Love" in 1990, while Laurie Miller released the 12" single "Parallels" on Atlantic Records and a second single "Love is a Natural Magical Thing" on Meet Me In Miami Records. Laurie evolved into a headline performer frequently showcasing her talents on cruises with a more intimate jazz style, and formed her own entertainment company called Xica productions. Casanas later resurfaced as a solo artist (Sandee) and released a solo album, Only Time Will Tell, which garnered the club hits "You're The One", "Love Desire", and the Clivilles & Cole-produced bassline-heavy hit "Notice Me". She continued to tour actively in dance clubs and freestyle shows, until her death on December 15, 2008, of a seizure at the age of 46. All three original members: Casanas, Lorenzo and Miller later contributed vocals on songs on the Miami group Will to Power's eponymous 1988 debut album. Gioia Bruno also provided lead vocals on Will to Power's 2004 album, Spirit Warrior.

Answer this question "What were their roles in the band?"
output:

Answer the question at the end by quoting:

Serebro (Russian: Serebro; English translation: Silver) (Stylized as SEREBRO) is a Russian girl group formed by their manager and producer Maxim Fadeev.
After the decline of their success after "Mama Lover", the group started to record songs for their third studio album. In January 2013, the group announced that they would release their further material in Japan after signing with EMI Music. They also announced that they plan to release a compilation entitled Serebration that includes songs from their first and second studio albums. The group traveled to Japan to promote the compilation album and to do a live concert tour. In March 2013, the group released their promotional single "Sexy Ass", but it failed to chart in Russia. In June 2013, the group released their single "Mi Mi Mi" which charted in Italy, peaking at 5 on the Italian iTunes chart. In July 2013, the group released the song "Malo Tebya". The song was released on Russian radio airplay on 10 July and marked a welcome return to the top ten in Russia for the band, ultimately peaking at number five. A new collaboration with DJ M.E.G., entitled "Ugar" (Ugar), has premiered on the band's Facebook page and the Promo DJ website on 18 September. The group announced that they signed a deal with Republic Records and Universal Music Group and discussed plans to re-release their single "Mi Mi Mi" as their first international single. On 28 September, member Anastasia Karpova confirmed her planned departure from the group. Karpova had told Fadeev months prior that she intended to leave the group. She noted that the decision was mutual with other members of the band and that her primary motivation was to pursue a solo career. A new member, named Dasha Shashina, was announced on 3 October 2013. Shashina had re-recorded Anastasia's recordings in the group's songs "Malo Tebya" and "Ugar", which is expected to release a video with Shashina featuring in it. Temnikova left the group in May 2014, ahead of her planned December exit, after having become pregnant. Karpova temporarily returned until newest member Polina Favorskaya was introduced on June 5, 2014. Serebro's 3rd studio album '925' was supposed to be released on iTunes Russia on 15 October 2015 but due to their studio harddrive being stolen, the album release had to be cancelled.

What projects were they working on
March 2013, the group released their promotional single "Sexy Ass", but it failed to chart in Russia.