LEISCHNER, P. Polibky kružnic: René Descartes a Alžběta Falcká. Matematika–Fyzika–Informatika, [S. l.], v. 24, n. 1, p. 17–23, 2015. Disponível em: http://158.194.80.143/index.php/mfi/article/view/177. Acesso em: 13 led. 2025.