http://www.bloomberg.com/news/articles/2015-06-30/it-s-a-bull-market-for-speed-trader-virtu-as-greece-roils-stocks

http://www.tradersmagazine.com/news/technology/is-your-exchange-ready-for-tonights-leap-second-114060-1.html

http://www.marketwatch.com/story/five-years-after-flash-crash-committee-to-fix-markets-can-barely-agree-an-agenda-2015-06-30

http://www.bloomberg.com/news/articles/2015-06-30/drama-in-s-p-500-charts-as-200-day-average-looms-with-vix-at-19

http://www.bloomberg.com/news/features/2015-06-30/ice-cme-carve-up-the-trading-business-a-tale-of-two-exchanges

http://www.investing.com/analysis/today%E2%80%99s-34-vix-spike-and-what-to-expect-going-forward-256653

http://www.reuters.com/article/2015/06/29/usa-puertorico-stocks-idUSL2N0ZF1OI20150629

http://www.reuters.com/article/2015/06/30/markets-forex-idUSL8N0ZG23E20150630

http://www.marketwatch.com/story/us-stocks-eye-higher-open-after-greek-led-selloff-2015-06-30?siteid=yhoof2

http://www.bloomberg.com/news/articles/2015-06-29/citigroup-overtakes-jpmorgan-as-biggest-u-s-derivatives-dealer

http://www.bloomberg.com/news/articles/2015-06-30/choose-your-own-fear-adventure

http://www.tulsaworld.com/washingtonpost/business/s-p-wipes-out-gain-for-year-as-greece-spurs/article_0e3f012e-0efb-56c5-a79c-abb1024ac6f5.html