PASTECZKA, P. Interval-type theorems concerning means. Annales Universitatis Paedagogicae Cracoviensis Studia Mathematica, [S. l.], v. 17, p. 37–43, 2018. Disponível em: https://studmath.uken.krakow.pl/article/view/12958. Acesso em: 21 jul. 2026.