The Beatles (album) stereo only. In the UK, the following album, "Yellow Submarine", was the last to be shipped in mono. The mono version of "The Beatles" was made available worldwide on 9 September 2009, as part of "The Beatles in Mono" CD boxed set. A reissue of the original mono LP was released worldwide in September 2014. The album's sleeve was designed by pop artist Richard Hamilton, in collaboration with McCartney. Hamilton's design was in stark contrast to Peter Blake's vivid cover art for "Sgt. Pepper's Lonely Hearts Club Band", and consisted of a plain white sleeve. The band's name, in Helvetica,
Sgt. Pepper's Lonely Hearts Club Band placement of random gibberish in the run-out groove, is one of the album's defining features. In Mark Lewisohn's opinion, "Sgt. Pepper" represents the group's last unified effort, displaying a cohesion that would begin deteriorating immediately following the album's completion and that had entirely disappeared by the release of "The Beatles" in 1968. Martin recalled in 1987 that throughout the making of "Sgt. Pepper", "There was a very good spirit at that time between all the Beatles and ourselves. We were all conscious that we were doing something that was great." He said that while McCartney effectively led the project, and