Focas, C. (1994). Fares compared: An international comparison of public transport fares. London Research Centre.
Chicago-viite (17. p.)Focas, C. Fares Compared: An International Comparison of Public Transport Fares. London Research Centre, 1994.
MLA-viite (9. p.)Focas, C. Fares Compared: An International Comparison of Public Transport Fares. London Research Centre, 1994.
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