When John Lennon released the iconic single "Imagine" in 1971, he was listed as the sole songwriter. He later admitted that his wife, Yoko Ono, inspired the concept and cowrote the lyrics.

John Lennon and ... started collaborating on songs almost as soon as they met, scribbling lyrics and chords in a notebook with every entry emblazoned: “ANOTHER LENNON-McCARTNEY ORIGINAL.” ...

Ian Leslie’s “John & Paul: A Love Story in Songs ... depressed Lennon and the more outgoing, driven and businesslike McCartney. Leslie’s comprehensive assembly of lyrics, memos and ...

This book cover image released by Celadon shows "John & Paul A Love Story in Songs ... Lennon and the more outgoing, driven and business-like McCartney. Leslie’s comprehensive assembly of lyrics ...

What songs might McCartney and Brian Wilson might have written, for example? Leslie so thoroughly dissects the relationship between Lennon and McCartney, though, that it is difficult to imagine ...