1. Problems associated with underground cavities in the Paris region;Arnould,1970
2. A revised weathering classification for Mercia Mudstone (Keuper Marl);Bacciarelli,1993
3. British Geological Survey, 1976. Loughborough, Sheet 141, Solid and Drift. 1:50000 (Southampton: Ordnance Survey for the British Geological Survey).
4. Cadilhac, M., Poupelloz, B., Toulemont, M., 1977. Fondations d'ouvrage d'art en site karstique. Le viaduc de l'autoroute A15. Bulletin de Liaison Labo. P. et Ch. 87. janv.-févr. Réf. 1915.
5. The effects of weathering on the shear strength properties of Keuper Marl;Chandler;Geotechnique,1969