Whittaker, B. N., & Frith, R. C. (1990). Tunnelling: Design, stability, and construction. London: Institution of Mining and Metallurgy.
Παραπομπή Chicago StyleWhittaker, Barry N., and Russell C. Frith. Tunnelling: Design, Stability, and Construction. London: Institution of Mining and Metallurgy, 1990.
Παραπομπή MLAWhittaker, Barry N., and Russell C. Frith. Tunnelling: Design, Stability, and Construction. London: Institution of Mining and Metallurgy, 1990.
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