Rivalry in the Anti-EU camp

Say what you like about referendums, but they are supposed to offer people a simple question, with just two options. So the UK will vote - perhaps in just a few months - on whether or not to stay in the European Union. Two options, two opposing sides, you might think. Except that the anti-EU side has split into different factions, firing insults at each other, rather than at their pro-EU opponents. Here's my report for BBC Radio from the north of England.