Results of a plebiscite in three Polish districts conducted between July 1920 and March 1921. Rocznik statystyki Rzeczypospolitej Polskiej linkArchived 2007-06-09 at the Wayback Machine(pdf, 623 KB). Główny Urząd Statystyczny Rzeczypospolitej Polskiej GUS, Annual (Main Statistical Office of the Republic of Poland) (1920/1922, part II). Retrieved on 2008-01-23.
herder-institut.de
the census results are published in Rocznik statystyki Rzczypospolitej Polskiej/Annuaire statistique de la République Polonaise 1 (1920/22), vol 2, Warszawa 1923, p. 358. pdfArchived 2013-07-22 at the Wayback Machine
Results of a plebiscite in three Polish districts conducted between July 1920 and March 1921. Rocznik statystyki Rzeczypospolitej Polskiej linkArchived 2007-06-09 at the Wayback Machine(pdf, 623 KB). Główny Urząd Statystyczny Rzeczypospolitej Polskiej GUS, Annual (Main Statistical Office of the Republic of Poland) (1920/1922, part II). Retrieved on 2008-01-23.
the census results are published in Rocznik statystyki Rzczypospolitej Polskiej/Annuaire statistique de la République Polonaise 1 (1920/22), vol 2, Warszawa 1923, p. 358. pdfArchived 2013-07-22 at the Wayback Machine
Historical abstracts: Twentieth century abstracts, 1914–2000: Volume 37 American Bibliographical Center, p. 743 – 1986
On 9 March 1920, Germans attacked the Polish consulate in the city of Allenstein (Olsztyn) [pl], as part of an anti-Polish campaign before the plebiscite on East Prussia that had been provided for by the Treaty of Versailles in 1919.
