Problem: Simon & Garfunkel were an American folk rock duo consisting of singer-songwriter Paul Simon and singer Art Garfunkel. They were one of the best-selling music groups of the 1960s and became counterculture icons of the decade's social revolution, alongside artists such as the Beatles, the Beach Boys, and Bob Dylan. Their biggest hits--including "The Sound of Silence" (1964), "Mrs. Robinson" (1968), "The Boxer" (1969), and "Bridge over Troubled Water" (1970)--reached number one on singles charts worldwide. Their often rocky relationship led to artistic disagreements, which resulted in their breakup in 1970.

The duo's fourth studio album, Bookends, was recorded in fits and starts over various periods from late 1966 to early 1968. The duo were signed under an older contract that specified the label pay for sessions, and Simon & Garfunkel took advantage of this indulgence, hiring viola and brass players, as well as percussionists. The record's brevity reflects its concise and perfectionist production. The team spent over 50 studio hours recording "Punky's Dilemma", for example, and re-recorded vocal parts, sometimes note by note, until they were satisfied. Garfunkel's songs and voice took a lead role on some of the songs, and the harmonies for which the duo was known gradually disappeared. For Simon, Bookends represented the end of the collaboration and became an early indicator of his intentions to go solo. Although the album had been planned long in advance, work did not begin in earnest until the late months of 1967. Prior to release, the band helped put together and performed at the Monterey Pop Festival, which signaled the beginning of the Summer of Love on the West Coast. "Fakin' It" was issued as a single that summer and found only modest success on AM radio; the duo were much more focused on the rising FM format, which played album cuts and treated their music with respect. In January 1968, the duo appeared on a Kraft Music Hall special, Three for Tonight, performing ten songs largely culled from their third album. Bookends was released by Columbia Records in April 1968. In an historical context, this was just 24 hours before the assassination of civil rights movement activist Martin Luther King Jr., which spurred nationwide outrage and riots. The album debuted on the Billboard Top LPs in the issue dated April 27, 1968, climbing to number one and staying at that position for seven non-consecutive weeks; it remained on the chart as a whole for 66 weeks. Bookends received such heavy orders weeks in advance of its release that Columbia was able to apply for award certification before copies left the warehouse, a fact it touted in magazine ads. The record became the duo's best-selling album to date: it fed off the buzz created by the release of The Graduate soundtrack album ten weeks earlier, creating an initial combined sales figure of over five million units. Davis had predicted this fact, and suggested raising the list price of Bookends by one dollar to $5.79, above the then standard retail price, to compensate for including a large poster included in vinyl copies. Simon instead scoffed and viewed it as charging a premium on "what was sure to be that year's best-selling Columbia album". According to biographer Marc Eliot, Davis was "offended by what he perceived as their lack of gratitude for what he believed was his role in turning them into superstars". Rather than implement Davis' price increase plan, Simon & Garfunkel signed a contract extension with Columbia that guaranteed them a higher royalty rate. The lead single "Mrs. Robinson" became, at the 1969 Grammy Awards the first rock and roll song to receive Record of the Year; it was also awarded Best Contemporary Pop Performance by a Duo or Group.

did they record another song in 1968?

Answer with quotes: In January 1968, the duo appeared on a Kraft Music Hall special, Three for Tonight, performing ten songs largely culled from their third album.

Problem: Charles Michael "Chuck" Schuldiner (May 13, 1967 - December 13, 2001) was an American singer, songwriter, and guitarist. He founded the pioneering band Death in 1983. Schuldiner is often referred to as "The Godfather of death metal", and his obituary in the January 5, 2002 issue of UK's Kerrang! magazine said that "Chuck Schuldiner was one of the most significant figures in the history of metal."

Schuldiner formed Death as Mantas in 1983 when he was just 16 years old. Original members were Schuldiner (guitar), Rick Rozz (guitar) and Kam Lee (drums and vocals). In January 1986, Schuldiner moved to Toronto and temporarily joined the Canadian band Slaughter. However, he quickly returned to continue the formation of Death. Death underwent many lineup changes. With Chris Reifert, Schuldiner eventually released the first Death album, titled Scream Bloody Gore, in 1987. He continued with 1988's Leprosy with the line-up of former Mantas guitarist Rick Rozz and rhythm section Terry Butler on bass and Bill Andrews on drums, and 1990's Spiritual Healing, where guitarist James Murphy had replaced the fired Rozz in 1989. After Spiritual Healing, Schuldiner stopped working with full-time band members, preferring to work with studio and live venue musicians, due to bad relationships with Death's previous rhythm section and guitarists. This earned Schuldiner something of a 'perfectionist' reputation in the metal community. Schuldiner had also fired his manager Eric Greif but settled and re-hired him before the recording of his next, influential release. Death's breakthrough album, Human saw the band evolving to a more technical and progressive style, in which Schuldiner displayed his guitar skills more than ever. He continued in this style (and continued the success of the band) with 1993's Individual Thought Patterns, 1995's Symbolic, and finally The Sound of Perseverance in 1998. Throughout his career, Schuldiner was not afraid to take on controversial lyrical subjects, taking an anti-drug stance on "Living Monstrosity" and writing about abortion in "Altering the Future". He put Death on hold after this to continue Control Denied, which he had been putting together prior to the release of The Sound of Perseverance, and released The Fragile Art of Existence in 1999. Control Denied also had other players from the latest Death album but featured a melodic metal vocalist. Schuldiner also played guitar in the "supergroup" Voodoocult on the album Jesus Killing Machine in 1994 and played a guest solo on Naphobia's 1995 release, Of Hell on the track "As Ancients Evolve" as a favor to the band's bassist at the time who was a friend of Schuldiner's. Schuldiner was also asked to be one of the many guest vocalists on Dave Grohl's 2001 Probot. Grohl, Napalm Death, Ozzy Osbourne, and Anthrax all increased efforts to raise funds for Schuldiner's medical bills with Grohl trying to involve Schuldiner on an album he was working on. In a 1999 interview Schuldiner spoke about why he didn't sing on the album The Fragile Art of Existence "...these vocals are all I ever wanted to do in Death but couldn't. I've had this dream of recording like that for years, and it seems like a dream come true. Tim Aymar is an amazing singer and this is the main difference. I think people will be surprised at the violence and strength of the album. Many people are expecting something like Iron Maiden, but, despite being one of my favorite bands, I didn't want to make an Iron Maiden-like album. I wanted to make an unpredictable album, just like I did in Death, I guess. I don't like to make predictable albums."

did he work with other bands or musicians?

Answer with quotes:
Control Denied also had other players from the latest Death album but featured a melodic metal vocalist. Schuldiner also played guitar in the "supergroup" Voodoocult