YOHAN, Yohan. Analisis Kurva Kalibrasi Colorimeter Sederhana Penentuan Ammonium pada Sampel Pupuk NPK. Piston: Journal of Technical Engineering, [S. l.], v. 4, n. 1, p. 42–47, 2020. DOI: 10.32493/pjte.v4i1.7358. Disponível em: https://openjournal.unpam.ac.id/index.php/Piston/article/view/7358. Acesso em: 22 dec. 2024.