Hoge, Patrick (May 23, 2011). "CrowdStar raises $23 million". San Francisco Business Times. Archived from the original on July 11, 2011. Retrieved December 19, 2012.
Hoge, Patrick (May 23, 2011). "CrowdStar raises $23 million". San Francisco Business Times. Archived from the original on July 11, 2011. Retrieved December 19, 2012.