National Research Council (U.S.). Highway Research Board. (1952). Highway sufficiency ratings: Presented at the 31st annual meeting, January 1952. The Board.
Chicago-viite (17. p.)National Research Council (U.S.). Highway Research Board. Highway Sufficiency Ratings: Presented at the 31st Annual Meeting, January 1952. Washington, D.C: The Board, 1952.
MLA-viite (9. p.)National Research Council (U.S.). Highway Research Board. Highway Sufficiency Ratings: Presented at the 31st Annual Meeting, January 1952. The Board, 1952.
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