Simon. In 1977, Garfunkel joined Simon for a brief performance of their songs on The Paul Simon Special, and later that year they recorded a cover of Sam Cooke's "(What a) Wonderful World" with James Taylor. Old tensions appeared to dissipate upon Garfunkel's return to New York in 1978, when the duo began interacting more often. On May 1, 1978, Simon joined Garfunkel for a concert held at Carnegie Hall to benefit the hearing disabled. By 1980, the duo's solo careers were not doing well. To help alleviate New York's economic decline, concert promoter Ron Delsener suggested a free concert in Central Park. Delsener contacted Simon with the idea of a Simon & Garfunkel reunion, and once Garfunkel had agreed, plans were made. The concert, held on September 19, 1981, attracted more than 500,000 people, at that time the largest ever concert attendance. Warner Bros. Records released a live album of the show, The Concert in Central Park, which went double platinum in the US. A 90-minute recording of the concert was sold to Home Box Office (HBO) for over $1 million. The concert created a renewed interest in Simon & Garfunkel's work. They had several "heart-to-heart talks", attempting to put their disagreements behind them. The duo undertook a world tour beginning in May 1982, but their relationship grew contentious; for the majority of the tour, they did not speak to one another. Warner Bros. pushed for the duo to extend the tour and release a new studio album. Simon had new material ready, and, according to Simon, "Artie made a persuasive case that he could make it into a natural duo record." However, the duo quarrelled again; Garfunkel refused to learn the songs in the studio and would not give up his longstanding cannabis and cigarette habits, despite Simon's requests. Instead, the material became Simon's 1983 album Hearts and Bones. A spokesperson said: "Paul simply felt the material he wrote is so close to his own life that it had to be his own record. Art was hoping to be on the album, but I'm sure there will be other projects that they will work on together." Another rift opened when the lengthy recording of Simon's 1986 album Graceland prevented Garfunkel from working with engineer Roy Halee on his Christmas album The Animals' Christmas (1985). In 1986, Simon said he and Garfunkel remained friends and got on well, "like