The first congress for world peace in Warsaw.
This is Czesław Słania's first work as an apprentice. He was allowed to engrave the metal part of the hammer under strict surveillance of M.R. Polak, the latter's name appearing in the stamp's lower right corner.
Polski kongres pokoju - Warszawa 1950 = Polish congress for peace - Warsaw 1950.
About Polish poster art
Tadeusz Gronowski (www.polishfilms.org)
Czesław Słania's engravings (by Ann Mette Heindorff)
Czesław Słania's personalised stamps