Dosparth Edeyrn Davod Aur, or, The ancient Welsh grammar which was compiled by royal command in the thirteenth century by Edeyrn the Golden tongued, to which is added Y pum llyfr kerddwriaeth, or The rules of Welsh poetry, originally compiled by Davydd Ddu Athraw, in the fourteenth, and subsequently enlarged by Simwnt Vychan, in the sixteenth century