Henneberg, Maciej, and Jerzy Kozak. “Seasonal Rythm of Births in an Rural XIXth Century Population: Parish of Szczepanowo (Bydgoszcz Voivodeship)”. Anthropological Review 42, no. 1 (January 1, 1976): 19–31. Accessed July 1, 2024. https://czasopisma.uni.lodz.pl/ar/article/view/20399.