Grzesik-Gąsior, J., E. Granisz, A. Bień, and E. Rzońca. “Midwife in the Prevention of Preterm Birth”. Journal of Education, Health and Sport, vol. 7, no. 8, Aug. 2017, pp. 1461-76, https://apcz.umk.pl/JEHS/article/view/5057.