Duncan, J. M. (2005). Soil strength and slope stability. New Jersey: John Wiley and Sons.
Dyfyniad Arddull ChicagoDuncan, J. Michael. Soil Strength and Slope Stability. New Jersey: John Wiley and Sons, 2005.
Dyfyniad MLADuncan, J. Michael. Soil Strength and Slope Stability. New Jersey: John Wiley and Sons, 2005.
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