GURNING, Kasta; LUMBANGAOL, Sifikal; SITUMORANG, Risanti F. R; SILABAN, Saronom. Determination of phenolic contents and antioxidant activity test of ethanol extract of Sirih merah (Piper crocatum Ruiz & Pav.) leaves using the DPPH method. Jurnal Pendidikan Kimia, [S. l.], v. 13, n. 2, p. 137–142, 2021. DOI: 10.24114/jpkim.v13i2.26984. Disponível em: https://jurnal.unimed.ac.id/2012/index.php/jpk/article/view/26984. Acesso em: 5 jul. 2025.