Swedish researchers have joined Danish colleagues in an attempt to establish Denmark's claims to parts of the Arctic region. The expedition follows the planting of a flag on the underwater Lomonosov Ridge by a Russian expedition last week. The expedition, led by Swedish icebreaker Oden, set off from Norway on Sunday. It is being led jointly by Martin Jakobsson of Stockholm University and Christian Marcussen of the Geological Survey of Denmark. The Danes claim that the ridge is on the same continental shelf as Greenland, which is a Danish territory. They hope that the expedition will prove the country's claim...