; . Jurnal Ilmiah Sains, [S. l.], v. 11, n. 1, p. 23–25, 2011. DOI: 10.35799/jis.11.1.2011.35. Disponível em: https://ejournal.unsrat.ac.id/v3/index.php/JIS/article/view/35. Acesso em: 19 apr. 2025.