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Lua i Stíl Chicago (17ú heag.)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.
Lua MLA (9ú heag.)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.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.