1. B. A. Stankiewicz and D. E. G. Briggs, Biogeochemistry Research Centre, Department of Geology, University of Bristol, Queen’s Road, Bristol BS8 1RJ, UK.
2. R. P. Evershed and M. B. Flannery, Organic Geochemistry Unit, School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, UK.
3. M. Wuttke, Landesamt für Denkmalpflege Rheinland-Pfalz, Referat Erdgeschichtliche Denkmalpflege, Am Obstmarkt 13, D-55126 Mainz, Germany.