Singh, B., & Goel, R. K. (2011). Engineering rock mass classification: Tunnelling, foundations, and landslides. Butterworth-Heinemann.
Chicago-viite (17. p.)Singh, Bhawani, ja R. K. Goel. Engineering Rock Mass Classification: Tunnelling, Foundations, and Landslides. Burlington, Mass.: Butterworth-Heinemann, 2011.
MLA-viite (9. p.)Singh, Bhawani, ja R. K. Goel. Engineering Rock Mass Classification: Tunnelling, Foundations, and Landslides. Butterworth-Heinemann, 2011.
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