Attewell, P. B., & Farmer, I. W. (1976). Principles of Engineering Geology. Chapman & Hall.
Dyfyniad Arddull ChicagoAttewell, P. B., and I. W. Farmer. Principles of Engineering Geology. London: Chapman & Hall, 1976.
Dyfyniad MLAAttewell, P. B., and I. W. Farmer. Principles of Engineering Geology. Chapman & Hall, 1976.
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