Major, M., & Nawolska, B. (2017). Nowe spojrzenie na gry Penneya. Annales Universitatis Paedagogicae Cracoviensis | Studia Ad Didacticam Mathematicae Pertinentia, 5, 83–94. Retrieved from https://didacticammath.uken.krakow.pl/article/view/3683