Poland is issuing commemorative coins this month to honor three Catholic-Polish families who were killed by the Nazis for having rescued Jews during the Holocaust.

The two coins, in denominations of two zlotys, worth about 65 cents, and 20 zlotys, worth about $6.50, will be issued by the National Bank of Poland on March 15. They honor the Ulma, Kowalski and Baranek families.

On March 15, 1943, German auxiliary police discovered eight Jews hidden in the home of Wincenty and Łucja Baranek, in the village of Siedliska. The police killed the Jews immediately and then shot the Baraneks and their two sons in the backs of their heads.

Adam and Bronisława Kowalski hid two Jewish neighbors in their house in the village of Ciepielów. Other Jews were hidden in other homes in the village. In December 1942, the Kowalskis, their five children and the Jews they were hiding were among at least 34 people killed when Nazi police, after being tipped off, set fire to houses where Jews were believed to be hidden.

Józef and Wiktoria Ulma hid eight Jews in the attic of their house in the village of Markowa for 18 months. After being informed on in 1944, the couple, their six children and the Jews they were hiding were all killed.

 It is “thanks to such people that about 30 thousand to 40 thousand Jews survived the occupation of Poland,” Jerzy Halbersztadt, the former director of the forthcoming Museum of the History of Polish Jews, wrote in the official brochure for the coins. “And although most of our fellow citizens did not know how to, or were unable to, resist the crimes, the accomplishments of the noblest and bravest people should give us the strength to cope with difficult problems in our history.”