HAY, W. W. (1977). An introduction to transportation engineering (2.). John Wiley & Sons.
Chicago-viite (17. p.)HAY, WILLIAN WALTER. An Introduction to Transportation Engineering. 2. New York: John Wiley & Sons, 1977.
MLA-viite (8. p.)HAY, WILLIAN WALTER. An Introduction to Transportation Engineering. 2. John Wiley & Sons, 1977.
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