Tretten, R. W. (1977). Cities in crisis: Decay or renewal? Prentice Hall.
Lua i Stíl Chicago (17ú heag.)Tretten, Rudie W. Cities in Crisis: Decay or Renewal? Prentice Hall, 1977.
Lua MLA (9ú heag.)Tretten, Rudie W. Cities in Crisis: Decay or Renewal? Prentice Hall, 1977.
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