The near rule-of-thumb for determining authorship of Beatles songs is this. Unless it's one of the rare occasions where Ringo is singing, or one of the handful of Lennon-McCartney songs George was given to sing early on when they didn't feel his songwriting was at an acceptable standard yet, the author of the song sang lead.
Written by Ken Burch
Retired Alaska ferryboat steward, grandparent, sometime poet. Radical yet independent of dogma. Likes nice days, playing banjo and not as yet dying of Covid.