Gwyn is a great little book which will give you a lot of insights on one of the mythical figures of Glastonbury Tor: Gwyn
ap Nudd (that you should pronounce "Neeth" and not "Nud"). Yuri Leitch explores the different hypotheses and the mystical role of Gwyn, only referred to as a "king of the fairies". The book is well documented and has received appraisal from authorities on the topic of Arthurian studies. The illustrations have been made by the author himself and they are just simply enchanting and evocative.