J.P. Firlej - Wicewójt roku 2001. Regional Barometer. Analyses & Prognoses, [S. l.], n. 1, p. 40–41, 2002. Disponível em: https://czaz.akademiazamojska.edu.pl/index.php/br/article/view/1789. Acesso em: 28 apr. 2025.