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"One aspect that makes this photo eye-catching is the lovely layout and plant diversity -- much more appealing than the usual green roof monoculture found in North America.  Who's behind the mystery roof?  It seems it is either on the Penn State"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/sustainable-product-design/center-for-green-roof-research-penn-states-ecoroof-technology-course.html>