Knowledge and opinions of medical staff on Natural Fertility Awareness Methods . Kwartalnik Naukowy Fides et Ratio, [S. l.], v. 32, n. 4, p. 215–232, 2017. Disponível em: https://fidesetratio.com.pl/ojs/index.php/FetR/article/view/628. Acesso em: 24 jun. 2025.