The belief that immigrants generate beneficial externalities in their host countries, specifically in the form of an increased opportunity and ability of firms to expand their foreign trade, has recently been challenged by George Borjas in Heaven?s Door (1999, p. 97) as having no empirical...

The belief that immigrants generate beneficial externalities in their host countries, specifically in the form of an increased opportunity and ability of firms to expand their foreign trade, has recently been challenged by George Borjas in Heaven's Door (1999, p. 97) as having no empirical...