1. Bluck B. J. (1978) in Crustal evolution in northwestern Britain and adjacent regions, Sedimentation in a late orogenic basin: the Old Red Sandstone of the Midland Valley of Scotland, eds Bowes D. R. Leake B. E. (Seel House Press, Liverpool), p 492.
2. Intrusive quartz latites in the Blaenau Ffestiniog area, Merioneth
3. The tectonic evolution of the Welsh Caledonides;Coward,1979
4. Intrusion of basaltic sills into highly porous sediments, and resulting hydrothermal activity
5. Eyles V. A. Simpson J. B. MacGregor A. G. (1949) Mem. geol. Surv. U. K, Geology of Central Ayrshire (H. M. S. O), p 160.