Gorwelion : cynllun Cymraeg fel iaith gyntaf yn yr ysgol uwchradd. Cyfres 1. Thema 3 : Ysbridion [i.e. Ysbrydion] a dirgelion. Nodiadau athrawon. Published by Gwasg y Dref Wen ar ran y Cyngor Ysgolion in 1983. Publication and catalogue information, links to buy online and reader comments.