1. ABAQUS (1998): Finite Element Program, from Hibbit, Karlson & Sorensen Inc., 1080 Main Street, Pawtucket, RI, USA.
2. Analytical Solutions for Shallow Tunnels in Saturated Ground
3. Effect of pore water pressure on tunnel support during static and seismic loading
4. Brekke, T. L., Ripley, B. D. (1985): Leakage from pressure tunnels and shafts. Waterpower. In: Roluti, M. J. (ed.) ASCE, New York, pp 1228–1237.
5. Brekke, T. L., Ripley, B. D. (1989): Geotechnical engineering challenges in the design of pressure tunnels and shafts. In: Cording, E. J., Hall, W. J., Haltiwanger, J. D., Hendron, A. J., Mesri, G. (eds.) The Art of Science of Geotechnical Engineering, Prentice Hall, pp. 521–535.