Analysis of information sources in references of the Wikipedia article "Pola Negri" in Vietnamese language version.
The exact spelling of her and her parents' names is complicated by the mandated use of Russian in government records in that part of [partitioned] Poland, when she was born. For instance, her father's last name is recorded as Халупец at the Lipno Office of Vital Records, which can be rendered in Polish as Chalupec, Chałupec, Chalupiec, or Chałupiec.
