National Research Council (U.S.). Highway Research Board. (1957). Pavement condition surveys: Suggested criteria. Highway Research Board.
Chicago-Zitierstil (17. Ausg.)National Research Council (U.S.). Highway Research Board. Pavement Condition Surveys: Suggested Criteria. Washington, D.C: Highway Research Board, 1957.
MLA-Zitierstil (9. Ausg.)National Research Council (U.S.). Highway Research Board. Pavement Condition Surveys: Suggested Criteria. Highway Research Board, 1957.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.