“Pauli Heikkilä, Estonians for Europe. National Activism for European Unification 1922-1991”. Zeitschrift für Ostmitteleuropa-Forschung 65, no. 2 (March 22, 2016): 296–298. Accessed October 31, 2026. https://openjournals.osmikon.de/zfo/article/view/10032.