Claim: The opera "Maria", by Roman Statkowski, was performed in various Polish cities between 1919 and 1965.
Evidence: Statkowski's two operas were Philaenis (or Filenis) (1897, first performed in 1904) and Maria (1903-4, first performed in 1906). The latter is based on a novel of the same name by Antoni Malczewski. It has achieved some popularity in its native country and has been performed in various Polish cities between 1919 and 1965.