@book{Bel,
 author = {Bellori},
 title = {Le vite de' pittori, scultori e architetti moderni},
 year = {1672},
}
@book{Nie72,
 author = {Nietzsche, Friedrich},
 title = {Die Geburt der Tragödie aus dem Geiste der Musik},
 year =  {1872},
}