Holtz, R. D., Kovacs, W. D., & Kovacs, W. d. (1981). An introduction to geotechnical engineering. Englewood Cliffs, N.J.: Prentice Hall.
Παραπομπή Chicago StyleHoltz, R. D., William D. Kovacs, and William d. Kovacs. An Introduction to Geotechnical Engineering. Englewood Cliffs, N.J.: Prentice Hall, 1981.
Παραπομπή MLAHoltz, R. D., William D. Kovacs, and William d. Kovacs. An Introduction to Geotechnical Engineering. Englewood Cliffs, N.J.: Prentice Hall, 1981.
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