IWANOWICZ-PALUS, Grażyna Jolanta, KRYSA, Justyna, KIPA, Magdalena, DZIADUSZEK, Katarzyna and ŻÓŁKIEWSKA, Beata. Physical activity in the perinatal period. Journal of Education, Health and Sport. Online. 31 August 2017. Vol. 7, no. 8, pp. 1272-1289. [Accessed 7 December 2023].