WYWIAŁ, Janusz L. On space sampling designs. Acta Universitatis Lodziensis. Folia Oeconomica, [S. l.], n. 292, p. 21–35, 2013. DOI: 10.18778/0208-6018.292.03. Disponível em: https://czasopisma.uni.lodz.pl/foe/article/view/26920. Acesso em: 22 dec. 2025.