National Research Council (U.S.). Transportation Research Board. (1990). Research problem statements: Operation, safety and maintenance of transportation facilities. Transportation Research Board, National Research Council.
芝加哥风格引文National Research Council (U.S.). Transportation Research Board. Research Problem Statements: Operation, Safety and Maintenance of Transportation Facilities. Washington, D.C: Transportation Research Board, National Research Council, 1990.
MLA引文National Research Council (U.S.). Transportation Research Board. Research Problem Statements: Operation, Safety and Maintenance of Transportation Facilities. Transportation Research Board, National Research Council, 1990.
警告：这些引文格式不一定是100％准确.