What Series A Crunch? Why Some Startups Are Immunehttp://www.pehub.com/192420/what-series-a-crunch-why-some-startups-are-immune/
http://www.cbinsights.com/blog/trends/seed-investing-report
Finally, actual data: Series A crunch will kill 1,000 companies, $1B in angel money http://pandodaily.com/2012/12/19/finally-actual-data-series-a-crunch-will-kill-1000-companies-1b-in-angel-money/