1. Flavigny E, Desrues J, Player B (1990) Note technique, le sable d’Hostun RF. Rev Fr Géotech 53:67–70
2. Houlsby GT, Psomas S (2001) Soil conditioning for pipe jacking and tunnelling: properties of sand/foam mixtures. In: Proceedings of Underground construction, I. International exhibition & symposium. London Docklands, UK, pp 128–138
3. Langmaack L (2000) Advanced technology of soil conditioning. North American Tunnelling Congress, Boston 2000, A.A Balkema, Rotterdam, Brookfield, 2000, p 525. ISBN: 90 5809 162 7
4. Langmaack L, Feng Q (2005) Soil conditioning for EPB machines: balance of functional and ecological properties. In: Erdem, Solak (eds) Underground space use: analyses of the past and lessons for the future. ISB 04 1575 452 9. 729-735
5. Milligan GWE (2000) Lubrification and soil conditioning in tunneling, pipe jacking and micro-tunneling. A state of the art review. Technical report, Geotechnical-consulting group.
http://www.civil.eng.ox.ac.uk/research/pipejack/pdf/soilcond