http://blogs.wsj.com/moneybeat/2015/06/29/vix-hits-four-month-high-on-greece-but-still-nowhere-near-panic/

http://www.reuters.com/article/2015/06/29/cftc-swaps-crossborder-idUSL2N0ZF1J920150629

http://www.bloomberg.com/news/articles/2015-06-29/worldwide-stock-volatility-soars-as-sleepy-vix-awakens-on-greece

http://blogs.wsj.com/moneybeat/2015/06/29/with-stocks-frozen-in-athens-a-greek-etf-plunges-in-u-s/

http://www.bloomberg.com/news/articles/2015-06-28/with-61-seconds-in-a-minute-markets-brace-for-trouble

http://www.marketwatch.com/story/why-the-cme-group-delayed-the-closing-of-pits-2015-06-24

http://www.thetradenews.com/News/Operations___Technology/Trading_tools/Complex_US_options_market_hampers_liquidity_-_report.aspx

http://www.reuters.com/article/2015/06/24/cme-landmark-options-idUSL3N0Z84DT20150624

http://www.marketwatch.com/story/us-stocks-set-for-sharp-losses-with-greece-on-brink-of-default-2015-06-29?siteid=yhoof2

http://online.barrons.com/articles/what-if-greece-defaults-1435377110

http://www.reuters.com/article/2015/06/26/us-gold-china-sge-idUSKBN0P610220150626

http://www.cboeoptionshub.com/2015/06/27/vix/