National Research Council (U.S.). Highway Research Board. Committee on Communications & National Research Council (U.S.). Highway Research Board. Committee on Motorist Services. (1971). Communications and emergency services: 6 reports. Highway Research Board, National Research Council.
Παραπομπή σε μορφή Chicago (17η εκδ.)National Research Council (U.S.). Highway Research Board. Committee on Communications και National Research Council (U.S.). Highway Research Board. Committee on Motorist Services. Communications and Emergency Services: 6 Reports. Washington, D.C: Highway Research Board, National Research Council, 1971.
Παραπομπή σε μορφή MLA (9th εκδ.)National Research Council (U.S.). Highway Research Board. Committee on Communications και National Research Council (U.S.). Highway Research Board. Committee on Motorist Services. Communications and Emergency Services: 6 Reports. Highway Research Board, National Research Council, 1971.