1. The most recent, and very thorough, analysis of Shakespeare’s use of classical material is Colin Burrow: Shakespeare & Classical Antiquity (Oxford: Oxford University Press, 2013). In any case, a great deal of painstaking work has gone into tracing Shakespeare’s relationship with his sources, and any decent edition of an individual play will provide details of the appropriate sources.
2. Graham Holderness, Bryan Loughrey and Andrew Murphy (eds): Shakespeare: The Roman Plays (Harlow: Longman, 1996), 169.
3. Robert S. Miola: Shakespeare’s Rome (1 st paperback edn, Cambridge: Cambridge University Press, 2004), 12–13.
4. There is a long tradition of critical work on this relationship. I have characterised it elsewhere; see Paul Innes, ‘Cymbeline and Empire’, Critical Survey (Vol. 19, No. 2, 2007), 1–18.
5. Coppelia Kahn: Roman Shakespeare: Warriors, Wounds, and Women (London and New York: Routledge, 1997), 160.