Walker, R. A. The planning function in urban government. The university of Chicago press.
Chicago-referens (17:e uppl.)Walker, Robert Averill. The Planning Function in Urban Government. The university of Chicago press.
MLA-referens (8:e uppl.)Walker, Robert Averill. The Planning Function in Urban Government. The university of Chicago press.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.