Beatles Session Musicians Who?

A dozen or so of us were hashing over old Beatle’s songs last week and it was amazing how many folks had heard that so-and-so played on this song and so-and-so on another. Outside of the obvious and well-documented contributions of an Eric Clapton or Billy Preston, there seemed to be little proof to the pudding regarding others. All this leads me to this question:

Does anyone know of an authoritative source which lists “who played what” on individual songs? I realize that the list may not be complete and “London Symphony” may have to suffice for some background stuff – but you get the picture. I do not want to believe, for example, that George did not appear at all on Blue Jay Way and I’d like to have some proof! ;(