http://arxiv.org/PS_cache/arxiv/pdf/110 ... 4937v1.pdf
http://en.wikipedia.org/wiki/Gravitatio ... antimatter
http://www.physorg.com/news/2011-08-dar ... acuum.html
http://www.physorg.com/news/2011-07-big ... atter.html
http://www.springerlink.com/content/g332701735121773/