Unionization in Canada and the United States: A Tale of Two Countries

W. Craig Riddell, Small Differences That Matter: Labor Markets and Income Maintenance in Canada and the United States (University of Chicago Press, 1993), chap. 4, https://www.nber.org/books-and-chapters/small-differences-matter-labor-markets-and-income-maintenance-canada-and-united-states/unionization-canada-and-united-states-tale-two-countries.