1. Andreev M (1993) History of the Bulgarian bourgeois state and law 1878–1917. Sofia, 1993, publishing house Sofia (Bulgarian)
2. Anil Kumar SV, Bawge G, Vinay Kumar BC (2021) An overview of industrial revolution and technology of industrial 4.0. Int J Res Eng Sci (IJRES) 9(1):64–71
3. Audretsch DB, Thurik AR (1999) Capitalism and democracy in the 21st century: From the managed to the entrepreneurial economy. J Evol Econ
4. Avramov R (2007) Communal capitalism. Through the Bulgarian economic past. Sofia, Bulgarian Science and Culture Foundation (Bulgarian)
5. Bagga P (2016) Business economics, NMIMS Global Access