Johnson, R. B., & Degraff, V. J. (1988). Principles of Engineering Geology. John Wiley.
Chicago Style aipamenaJohnson, Robert. B., and V. Jerome Degraff. Principles of Engineering Geology. New Delhi: John Wiley, 1988.
MLA aipamenaJohnson, Robert. B., and V. Jerome Degraff. Principles of Engineering Geology. John Wiley, 1988.
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