Union Membership Density and Wages: The Role of Worker, Firm, and Job-Title Heterogeneity 18.67
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Journal of Econometrics, vol. 233, 2023, p. 612-632.

Unions and Collective Bargaining in the Wake of the Great Recession: Evidence from Portugal 10.92
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British Journal of Industrial Relations, vol. 55, 2017, p. 551-576.