Gerrit Voerman[in Dutch]; Dirk Strijker; Ida Terluin (2015). "Contemporary Populism, the Agrarian and the Rural in Central Eastern and Western Europe". In Sarah de Lange[in Dutch] (ed.). Rural Protest Groups and Populist Political Parties. Wageningen Academic Publishers. p. 172. doi:10.3920/978-90-8686-807-0. ISBN9789086862597.
Mateusz Piskorski[in Polish] (2010). Samoobrona RP w polskim systemie partyjnym (in Polish) (Dissertation ed.). Poznań: Adam Mickiewicz University in Poznań. p. 181.
nl.wikipedia.org
Gerrit Voerman[in Dutch]; Dirk Strijker; Ida Terluin (2015). "Contemporary Populism, the Agrarian and the Rural in Central Eastern and Western Europe". In Sarah de Lange[in Dutch] (ed.). Rural Protest Groups and Populist Political Parties. Wageningen Academic Publishers. p. 172. doi:10.3920/978-90-8686-807-0. ISBN9789086862597.