Question: What is the date of death of Helena Unierzyska's father?
Sentence (from "Jan Matejko"): His works include large oil on canvas paintings like "Rejtan" (1866), "Union of Lublin" (1869) or "Battle of Grunwald" (1878), numerous portraits, a gallery of Polish kings, and murals in St. Mary's Basilica, Kraków.
Relevant evidence: No