National Research Council (U.S.). Highway Research Board. (1957). Pavement condition surveys: Suggested criteria. Highway Research Board.
Lua i Stíl Chicago (17ú heag.)National Research Council (U.S.). Highway Research Board. Pavement Condition Surveys: Suggested Criteria. Washington, D.C: Highway Research Board, 1957.
Lua MLA (9ú heag.)National Research Council (U.S.). Highway Research Board. Pavement Condition Surveys: Suggested Criteria. Highway Research Board, 1957.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.