PAN

PAN

Letter to the Polish Academy of Science written 31.03.1965

Letter from Stefan Żółkiewski written in 12.02.1966

Letter from Stefan Żółkiewski written in 26.05.1964

Letter from Ksawery Piwocki written 11.11.1964

Letter to the Polish Academy of Science written 28.04.1964

Letter from Adam Schaff written 12.06.1962

Certificate from Irena Krońska written in 10.06.1955

Letter to Stefan Żółkiewski written in 23.12.1965 (a)

Postcard from Stefan Morawski written 05.12.1965

Letter to the Polish Academy of Science written 11.03.1965

Letter to Tadeusz Kotarbiński written 22.11.1948

Letter to the Polish Academy of Science written 16.11.1968