Welsh manuscript collection of religious texts, mainly in the hand of Hywel Fychan. Other parts of the original manuscript are are in Peniarth MS 12 and Cardiff MS 3.242.
- c.1400
- , Hywel Fychan ap Hywel Goch
- s. xv2
- , Gutun Owain
- 1783
- William Owen Pughe
- c. 1250
- s. xiv1
- Anonymous [hand in Harl. 4353, Cot. Cleo. A xiv and Book of Taliesin]
- s. xivmed
- c. 1350
- xiiimed
Welsh paper manuscript (434 pp.) written by Syr Huw Pennant around or by 1514.
- c.1514
- , Huw Pennant [Syr]
Manuscript known best as the Book of Aneirin (Llyfr Aneirin), containing the heroic poem Y Gododdin and a number of gorchanau.
- s. xiii2
Latin text of Welsh law, which was known to lawyers active in Gwynedd during the 13th century. This text or a related one may have provided the basis for the Latin text in London, British Library, MS Cotton Vespasian E xi, which refers to matters relating to both Gwynedd and south-west Wales. It has been suggested that the Llyfr y Tŷ Gwyn text became known in Gwynedd through the agency of Cadwgan, bishop of Bangor (1215-1236) and abbot of Whitland before that.
- s. xiv-xv
- , Anonymous [scribe I of Llyfr Coch Hergest], Hywel Fychan ap Hywel Goch, Anonymous [scribe of Llyfr Teg]
- 1346
- , Anonymous [anchorite of Llandewi Brefi]
