Preston, R. E. Transition zone structure: The three-sector hypothesis. Town Planning Review.
Cita Chicago (17th ed.)Preston, Richard E. "Transition Zone Structure: The Three-sector Hypothesis." Town Planning Review .
Cita MLA (9th ed.)Preston, Richard E. "Transition Zone Structure: The Three-sector Hypothesis." Town Planning Review, .
Atenció: Aquestes cites poden no estar 100% correctes.