1. Al Hallak, P., 1999. Etude expérimentale et numérique du reinforcement du front de taille par boulonnage dans les tunnels en terrain meuble, Doct. Thesis, Ecole Nationale des Ponts et Chaussées, Paris, France
2. Arsena, F.P., Focaracci, A., Lunardi, P., Volpe, A., 1991. La prima applicazione in Italia del pretaglio meccanico, Int. Congr. on Soil and Rock Improvement in Underground Works, Milano, 649–556
3. Brandl, H., 2000. Ground support—reinforcement—composite structures, Keynote Lecture, GeoEng 2000
4. Stability of clay in vertical openings;Broms;J. Soil Mech. Fdns. Div. ASCE,1967
5. Calvello, M., Taylor, R.N., 1999. Centrifuge modeling of a spile-reinforced tunnel heading, Int. Symp. Geotechnical Aspects of Underground Construction in Soft Ground. Tokyo, 345–350