http://frank-media.info/de/teil-c/windenergie/neue-designs-und-rotorformen.html
http://www.treehugger.com/files/2005/01/freedom_tower_g.php
http://www.grupotorcello.com.ar/ABAF/index.htm
http://www.treehugger.com/galleries/2009/03/stunning-green-buildings-in-china.php
http://www.andrewwatkins.us/projects/tall-buildings-in-the-city/
http://mrgreenbiz.wordpress.com/2008/10/05/innovative-tower-to-feature-atrium-of-wind-turbines/