Piatkowska, M. E. (2012). Self-rated physical activity level across Europe: Poland and other European countries. Biology of sport, 29(1), S. 23-31. https://www.termedia.pl/Original-paper-SELF-RATED-PHYSICAL-ACTIVITY-LEVEL-r-nACROSS-EUROPE-POLAND-AND-OTHER-r-nEUROPEAN-COUNTRIES,78,23369,1,1.html

Piatkowska, Monika Ewa. "Self-rated Physical Activity Level Across Europe: Poland and Other European Countries." Biology of Sport 29, no. 1 (2012): S. 23-31.

Piatkowska, Monika Ewa. "Self-rated Physical Activity Level Across Europe: Poland and Other European Countries." Biology of Sport 29.1 (2012): S. 23-31.