One better in line with the overall picture and free of political constraints :
Decades ago, Gutorn Gjessing pointed out that the identical [Red Paint] culture was found in Norway. No one paid much attention to that, but more recent carbon-14 dating has shown that the identical cultures had identical dates, and people began to pay more attention. It is now admitted that this is a high latitude culture that obviously sailed the stormy north Atlantic and stretched from northwest Europe over to America. It seemingly extends from along the Atlantic coast of Europe to America and in America from the high latitudes of Labrador down into New York state.
The dates are mind-boggling: 7,000 years ago both in Europe and America. That is 2,000 years earlier than the Great Pyramids of Egypt. It is at least 4,000 years earlier than the Mound Builders of the Ohio Valley. The evidence is cummulative, varied in nature, and most probably highly reliable.
http://www.science-frontiers.com/sf073/sf073a01.htm