Purvis, R. L. (1994). Underwater bridge maintenance and repair. National Academy Press.
Dyfyniad Arddull ChicagoPurvis, Ronald L. Underwater Bridge Maintenance and Repair. Washington, D.C: National Academy Press, 1994.
Dyfyniad MLAPurvis, Ronald L. Underwater Bridge Maintenance and Repair. National Academy Press, 1994.
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