1. The possible mechanics of convolute lamination in graded sand beds;Allen;Journal of the Geological Society, London,1977
2. Sedimentary Structures: Their Character and Physical Basis;Allen,1982
3. An interpretation and analysis of recumbent-folded deformed cross-bedding;Allen;Sedimentology,1972
4. Heol Senni Quarry, Powys;Barclay,2005
5. Geology of the Talgarth district – a brief explanation of the geological map. Sheet explanation of the British Geological Survey 1:50000 Sheet 214 Talgarth (England and Wales);Barclay,2003