1. Engels F. The making of the English working class. Leipzig; 1845.
2. Marx K, Engels F. The German ideology. Moscow: Marx-Engels Institute; 1932.
3. Josephson M. The robber barons: the great American capitalists. New York: Harcourt Brace and Company; 1934.
4. Fiorina M. Unstable majorities: polarization, Party sorting and political stalemate. Palo Alto: Hoover Press; 2017.
5. Saltman R, Figueras J, editors. European health care reform: analysis of current strategies. Copenhagen: WHO Regional Office for Europe; 1997.