461561 Kirby, R. F. (1974). Road user charges - some practical considerations. Washington : Urban Institute.
Chicago-viite (17. p.)461561 Kirby, Ronald F. Road User Charges - Some Practical Considerations. Washington : Urban Institute, 1974.
MLA-viite (9. p.)461561 Kirby, Ronald F. Road User Charges - Some Practical Considerations. Washington : Urban Institute, 1974.
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