Preston, R. E. Transition zone structure: The three-sector hypothesis. Town Planning Review.
Chicago-referens (17:e uppl.)Preston, Richard E. "Transition Zone Structure: The Three-sector Hypothesis." Town Planning Review .
MLA-referens (9:e uppl.)Preston, Richard E. "Transition Zone Structure: The Three-sector Hypothesis." Town Planning Review, .
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.