1. Aristophanes,Frogs, 721–726
2. M.M. Archibald, ‘Fishpool, Blidworth (Nottinghamshire), 1966 Hoard: Inerim Report’, Numismatic Chron., 7th Series, 1967,7, 133–146
3. W.A. Oddy, unpublished data
4. H. Rackham, ‘Pliny. Natural History’, Vol. IX, Loeb Classical Library, London, 1952 (reprinted 1968), p. 77
5. R. Halleux, ‘Les Alchimistes Grecs’, Tome 1, Papyrus de Leyde, Papyrus de Stockhom, Fragments de Recettes, Société d’Edition Les Belles Lettres, Paris, 1981. See pp. 22–24 for a discussion of the date