KUŘINA, F. Wallas - Polya - Hadamard and creativity. Annales Universitatis Paedagogicae Cracoviensis Studia Mathematica, [S. l.], v. 3, p. 125–132, 2003. Disponível em: https://studmath.uken.krakow.pl/article/view/13478. Acesso em: 30 oct. 2026.