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3. Bassett D. A. (1969) in The Pre Cambrian and Lower Palaeozoic rocks of Wales, Some of the major structures of early Palaeozoic age in Wales and the Welsh Borderland: An historical essay, ed Wood A. (University of Wales Press, Cardiff), pp 67–116.
4. The stratigraphy of the Bala district, Merionethshire
5. Bassett M. G. (1980) International Geological Congress Institute of Geological Sciences, London, (1980, Paris), in United Kingdom: Introduction to General Geology and Guides to Excursions 002, 055, 093 & 151, The Caledonides of Wales, the Welsh Borderland, and Central England, ed Owen T. R. pp 34–48.