Sagan, Adam. “GRAPHICAL APPROACH TO AGE-PERIOD-COHORT ANALYSIS”. Acta Scientiarum Polonorum. Oeconomia 20, no. 2 (December 21, 2021): 69-77. Accessed April 16, 2024. https://js.wne.sggw.pl/index.php/aspe/article/view/5023.