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2. Beckman, Ludvig. The Frontiers of Democracy. London : Palgrave-MacMillan, 2009.
3. Beitz, Charles. Political Equality: An Essay on Democratic Theory. Princeton : Princeton University Press, 1989
4. Brandt, Christopher, Linzer, Isabel, O’toole, Shannon, Puddington, Arch, Repucci, Sarah, Roylance, Tyler, Schenkkan, Nate, Shahbaz, Adrian, Slipowitz, Amy & Watson, Caitlin. Democracy in Retreat: Freedom in the World 2019 [online], 2019. Availabe at : https://freedomhouse.org/sites/default/files/Feb2019_FH_FITW_2019_Report_ForWebcompressed.pdf
5. Brennan, Jason. Against Democracy. Princeton : Princeton University Press, 2016