Engineering News 9 July 2010.

German technology giant Siemens has commissioned the Economist Intelligence Unit (EIU) to compile an ‘African Green City Index’ by the beginning of 2011, ranking the greenest cities in 12 African countries, including four South African cities…

http://www.engineeringnews.co.za/article/four-sa-cities-earmarked-for-big-africa-green-city-review-2010-07-09