Dyfyniad APA

National Research Council (U.S.). Highway Research Board. (1957). Pavement condition surveys: Suggested criteria. Highway Research Board.

Dyfyniad Arddull Chicago

National Research Council (U.S.). Highway Research Board. Pavement Condition Surveys: Suggested Criteria. Washington, D.C: Highway Research Board, 1957.

Dyfyniad MLA

National Research Council (U.S.). Highway Research Board. Pavement Condition Surveys: Suggested Criteria. Highway Research Board, 1957.

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