Olson, L. D. (1996). Nondestructive testing of unknown subsurface bridge foundations: Results of NCHRP Project 21-5. Transportation Research Board, National Research Council.
Chicago-viite (17. p.)Olson, Larry D. Nondestructive Testing of Unknown Subsurface Bridge Foundations: Results of NCHRP Project 21-5. Washington, D.C: Transportation Research Board, National Research Council, 1996.
MLA-viite (9. p.)Olson, Larry D. Nondestructive Testing of Unknown Subsurface Bridge Foundations: Results of NCHRP Project 21-5. Transportation Research Board, National Research Council, 1996.
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