similar to Paul McCartney's composition.
Greco said McCartney and fellow band-member John Lennon had an 'encyclopaedic knowledge' of world music and were particularly fond of Neapolitan songs.
Recorded in 1965, Yesterday is one of the Beatles' best-known songs. According to the Guinness Book of Records, it has the most cover versions of any song ever written.
McCartney once said he dreamt of the ballad while staying over at his girlfriend's house in a London flat.
Beatles biographies say McCartney was initially concerned that he had subconsciously plagiarised the song.
'For about a month I went round to people in the music business and asked them whether they had ever heard it before.
'Eventually it became like handing something in to the police. I thought if no one claimed it after a few weeks then I could have it,' a book by Craig Cross quotes McCartney as saying.
This is not the first time that music experts have noted similarities between Yesterday and other songs.
Three years ago, British musicologist Spencer Leigh told the BBC the song appeared to have been inspired by Nat King Cole's Answer Me.
McCartney's publicists later denied any resemblance between Answer Me and Yesterday.
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they knew Neapolian songs?
