travel costs

travel costs

Letter from Konstanty Michalski written 09.02.1939

Letter from Konstanty Michalski written 20.12.1937

Letter from Tadeusz Czeżowski written 01.06.1950

Letter from Stefan Żółkiewski written in 13.12.1966

Letter to the Polish Academy of Science written 01.07.1963

Letter to the Polish Academy of Science written 04.06.1966