1. Barzilai, A. (2000). Improving a geophone to produce an affordable broadband seismometer. Ph.D. Thesis, Stanford University.
2. Brincker, R., Lago, T., Andersen, P. & Ventura, C. (2001). Improving the classical geophone sensor element by digital correction. Proceedings: IMAC-XXIII Conference & Exposition on Structural Dynamics.
3. Modern railway track;Esveld,2001
4. Ebersöhn, W. & Selig, E.T. (1994). Track modulus measurements on a heavy haul line. Transportation Research Record 1470, TRB, National Research Council, Washington D.C.
5. Fröhling, R.D. (1997). Deterioration of railway track due to dynamic vehicle loading and spatially varying track stiffness. PhD-Thesis, University of Pretoria, South Africa.