PIĄTEK, B. On asymptotic cyclic contractions. Annales Universitatis Paedagogicae Cracoviensis Studia Mathematica, [S. l.], v. 9, p. 79–86, 2010. Disponível em: https://studmath.uken.krakow.pl/article/view/13248. Acesso em: 29 oct. 2026.