Task: Question Answering
Input (English): Passage: Martin's first recording session with the Beatles took place at EMI's Abbey Road Studios in London on 6 June 1962. Martin immediately complained to Epstein about Best's poor drumming and suggested they use a session drummer in his place. Already contemplating Best's dismissal, the Beatles replaced him in mid-August with Ringo Starr, who left Rory Storm and the Hurricanes to join them. A 4 September session at EMI yielded a recording of "Love Me Do" featuring Starr on drums, but a dissatisfied Martin hired drummer Andy White for the band's third session a week later, which produced recordings of "Love Me Do", "Please Please Me" and "P.S. I Love You".Martin initially selected the Starr version of "Love Me Do" for the band's first single, though subsequent re-pressings featured the White version, with Starr on tambourine. Released in early October, "Love Me Do" peaked at number seventeen on the Record Retailer chart. Their television debut came later that month with a live performance on the regional news programme People and Places. After Martin suggested rerecording "Please Please Me" at a faster tempo, a studio session in late November yielded that recording, of which Martin accurately predicted, "You've just made your first No.1."In December 1962, the Beatles concluded their fifth and final Hamburg residency. By 1963, they had agreed that all four band members would contribute vocals to their albums – including Starr, despite his restricted vocal range, to validate his standing in the group. Lennon and McCartney had established a songwriting partnership, and as the band's success grew, their dominant collaboration limited Harrison's opportunities as a lead vocalist. Epstein, in an effort to maximise the Beatles' commercial potential, encouraged them to adopt a professional approach to performing. Lennon recalled him saying, "Look, if you really want to get in these bigger places, you're going to have to change – stop eating on stage, stop swearing, stop smoking ..." Lennon said: "We used to dress how we liked, on and off stage. He'd tell us that jeans were not particularly smart and could we possibly manage to wear proper trousers, but he didn't want us suddenly looking square. He'd let us have our own sense of individuality.". 
Question: What group agreed that all four band members would contribute vocals to their albums?
Output (English): the Beatles.