Dillon, R. W. (1970). Legal and political aspects of free transit in major metropolitan areas. Northwestern University.
Chicago-viite (17. p.)Dillon, Robert W. Legal and Political Aspects of Free Transit in Major Metropolitan Areas. Evanston, Ill.: Northwestern University, 1970.
MLA-viite (8. p.)Dillon, Robert W. Legal and Political Aspects of Free Transit in Major Metropolitan Areas. Northwestern University, 1970.
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