Postcard from Edmund Husserl written 19.08.1932

Letter from Władysław Tatarkiewicz written 06.12.1938

Postcard from Stanisław Ignacy Witkiewicz written 19.10.1935

Letter from Tadeusz Czeżowski written 21.01.1925

Letter from Władysław Witwicki written 8.04.1925

Postcard from Tadeusz Czeżowski written 22.02.1958

Postcard from Wacław Borowy written 23.01.1948, pp.1,2

Letter to Kazimierz Twardowski written 08.07.1923

Letter to Kazimierz Twardowski written 08.03.1930

Letter from Stanisław Wędkiewicz written 28.05.1948

Letter from Kazimierz Twardowski written 31.12.1927

Protocol from the meeting of the PPS Board 12.05.1957