Under an agreement between the two leader of the Beatles, John Lennon and Paul McCartney, all the original songs of the group were officially registered as compositions of both (with Lennon, founder of the group, in the first place), but of course in reality many songs were composed by one or other of the two musicians.
Only a relatively small number of songs were actually written together. In many cases, the real authorship is known since the main (Yesterday and Let It Be by Paul, Lucy In The Sky with Diamonds and Norwegian Wood by John), but in other cases the authorship of the compositions was discovered only after the patient work of fans.
In particular, thanks to the work of the Swedish fan Myrsten, it is available for a long time a complete list of all the compositions of the quartet, with the indication of the author and lead vocal, available in different websites, including the site of Myrsten Penny Lane . The list contains some assumptions on which the opinions are not unanimous. Music-Graffiti, thanks to the the support of correspondents and fans who write to us can integrate the available information including here a more detailed and updated summary.
The uncertainty depends mainly on the different assessment of the work in the recording studio, during which the pieces chosen from one or other of the musicians were subjected to the others members, that maybe helped with additions and variations. So Paul has developed the famous chorus of "Lucy In The Sky" and John has developed the central part of "Michelle", both of these famous pieces can then be attributed to the couple rather than the individual.
