RURI PRIHATINI LUBIS; MUHERI INDRA AJA NASUTION. Analysis of the Effect of Using a Natural Water Filter on the Efficiency of Household Expenditure and Customer Satisfaction at Perumda Tirtanadi in Hamparan Perak Sub-District . Jurnal Teknik Indonesia, [S. l.], v. 5, n. 01, p. 118–128, 2026. DOI: 10.58471/ju-ti.v5i01.1013. Disponível em: https://jurnal.seaninstitute.or.id/index.php/juti/article/view/1013. Acesso em: 9 jul. 2026.