MITROVICA, Kosovo -- Serbs in northern Kosovo voted Tuesday in a referendum that is likely to overwhelmingly reject Kosovo's ethnic Albanian rule, further hindering Serbia's attempts to join the European Union. The EU, and even Serbia - which does not recognize Kosovo's declaration of independence in 2008 - have urged the Serbs not to stage the two-day referendum that asks whether they accept Kosovo's government. Serbs in the tense north last summer set up...