Letter from Kazimierz Twardowski written 10.02.1924

Letter to Kazimierz Twardowski written 04.11.1923

Letter to Kazimierz Twardowski written 23.12.1931

Postcard from Kazimierz Ajdukiewicz written 18.12.1922

Letter from Halina Poświatowska written 16.12. N/D

Letter from Mieczysław Wallis written 03.12.1969

Postcard from Halina Poświatowska written 20.12.1966

Postcard from Edmund Husserl written 24.12.1921

Postcard from Stanisław Ignacy Witkiewicz written 24.12.1937

Postcard from Henryk Elzenberg written 19.12.1963

Letter from Józef Tischner written 05.12.1968

Letter from Władysław Tatarkiewicz written 12.12.1966