Oxford, Bodleian Library MS. Digby 218. 109 folios. Parchment. 13th and 14th Centuries. 3. Roger Bacon Opus Minus. f57. 13. [Two folios with diagrams from the Ars Notoria 'tercia figura grammatice', the first and second 'nota dyaletice', and 'prima figura artis rethorice'.]