[url=http://www.state.gov/r/pa/prs/ps/2012/12/202065.htm]U.S.-Canada Visa and Immigration Information-Sharing Agreement[/url]
Помнится тут как то обсуждали возможность въезда через Канаду после проблем с американской визой. Теперь точно не получится.This agreement will enable Canada and the United States to share information from third country nationals who apply for a visa or permit to travel to either country.
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Under the agreement, information will not be shared regarding U.S. or Canadian citizens or permanent residents.