Não informado. (1974). Directory. Transportation Research Board, National Research Council.
Chicago-Zitierstil (17. Ausg.)Não informado. Directory. Washington: Transportation Research Board, National Research Council, 1974.
MLA-Zitierstil (8. Ausg.)Não informado. Directory. Transportation Research Board, National Research Council, 1974.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.