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2. Abshire M.S. (2002). "Differential Moisture Migration and Heave Beneath Slabs over Dripping Expansive Shale." MS thesis Colorado State University Fort Collins CO.
3. Non-linear soil stiffness in routine design
4. Colorado Department of Public Health and Environment (2009) "Fourth Annual Report to the Transportation Legislation Review Committee on the Status of Waste Tire Recycling In Colorado for Calendar Year 2008.
5. Dunham-Friel J.S. (2009). "Shear Strength and Stiffness of Expansive Soil and Rubber (ESR) Mixtures in Undrained Axisymmetric Compression." MS thesis. Colorado State University Fort Collins CO.