Riddell, R. (2004). Sustainable urban planning: Tipping the balance. Blackwell.
Lua i Stíl Chicago (17ú heag.)Riddell, Robert. Sustainable Urban Planning: Tipping the Balance. Oxford: Blackwell, 2004.
Lua MLA (9ú heag.)Riddell, Robert. Sustainable Urban Planning: Tipping the Balance. Blackwell, 2004.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.