Não informado. (1938). Traffic Engineering. Institute of Traffic Engineering.
Lua i Stíl Chicago (17ú heag.)Não informado. Traffic Engineering. New York: Institute of Traffic Engineering, 1938.
Lua MLA (8ú heag.)Não informado. Traffic Engineering. Institute of Traffic Engineering, 1938.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.