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2. 2) Schmidt, B.: Settlements and ground movements associated with tunnelling in soil, Ph. D. Thesis, Univ. of Illinois Urbana, 1969.
3. 3) Peck, R. B.: Deep excavations and tunnelling in soft ground, Proc. 7th ICSMFE, Mexico City, Mexico, pp. 225-290, 1969.
4. 4) Attewell, P. B.: Engineering Contract, Site Investigation, and Surface Movements in Tunnelling Works Soft Ground Tunnelling Failure and Displacements, pp. 5-12, A. A. Balkema 1981.
5. 5) O'Reilly, M. P. and New, B. M.: Settlements above tunnels in the United Kingdom-Their Magnitude and Prediction, Tunnelling'82, The Institution of Mining and Metallurgy, pp. 173-181, 1982.