MAČYS, Juozas Juvencijus. Geometrical reasoning in the determination of the order of factorial. Lietuvos matematikos rinkinys, [S. l.], v. 48, n. proc. LMS, p. 109–114, 2008. DOI: 10.15388/LMR.2008.19. Disponível em: https://www.journals.vu.lt/LMR/article/view/18073. Acesso em: 16 apr. 2025.