$1 Million Milestone Hit
San Diego Union-Tribune, March 6, 2013
San Diego Union-Tribune, March 6, 2013
Time, March 5, 2013
San Diego Union-Tribune, March 4, 2013
New Scientist, March 4, 2013
New York Times, March 3, 2013
San Diego Union-Tribune, March 2, 2013
The Seattle Times, February 28, 2013
San Diego Union-Tribune, February 25, 2013
San Diego Union-Tribune, February 24, 2013
The Washington Post, February 23, 2013