1. Ukraine ends transit of Russian gas to EU  BBC.com
2. Russia Suspends Flow of Natural Gas to Europe Through Ukraine  The New York Times
3. Russia halts gas exports to Europe via Ukraine  Reuters
4. Gazprom Reduces European Gas Flows Ahead of Transit Deal Expiration  The Moscow Times
5. Gazprom Says Gas Flows Via Ukraine Halted  Bloomberg

Source: Google Finance – Market News