Wigan, M. R., & Walmsley, D. A. (1972). A modal split model for long distance travel. Transport and Road Research Laboratory.
Chicago Style aipamenaWigan, M. Ramsay, and D. A. Walmsley. A Modal Split Model for Long Distance Travel. Crowthorne, Berkshire, [Eng.]: Transport and Road Research Laboratory, 1972.
MLA aipamenaWigan, M. Ramsay, and D. A. Walmsley. A Modal Split Model for Long Distance Travel. Transport and Road Research Laboratory, 1972.
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