Helmer Pedersen, E. (1983) “Keijo Virtanen: Settlement or Return. Finnish Emigrants (1860-1930) in the International Overseas Migration Movement. Migration Studies C 5. Turku, The Migration Institute, 1979. 275 s”., Historisk Tidsskrift, 14. Tilgængelig hos: https://tidsskrift.dk/historisktidsskrift/article/view/52598 (Set: 5 december 2025).