Não informado. (1931). Highway research abstracts. National Research Council, Highway Research Board.
Citação do estilo Chicago (17ª ed.)Não informado. Highway Research Abstracts. Washington: National Research Council, Highway Research Board, 1931.
Citação MLA (8ª ed.)Não informado. Highway Research Abstracts. National Research Council, Highway Research Board, 1931.
警告：这些引文格式不一定是100％准确.