The world's biggest banks including Citi and Goldman Sachs will draft in senior traders to work through the night following Britain's referendum on EU membership, set to be among the most volatile 24 hours for markets in a quarter of a century. A vote to leave the European Union on June 23 would spook investors by undermining post-World War Two attempts at European integration and placing a question mark over the future of the United Kingdom and its $2.9 trillion economy. Citi, Deutsche Bank, JPMorgan, Goldman Sachs, HSBC, Barclays, Royal Bank of Scotland and Lloyds are among those banks planning to have senior staff ... (full story)