Effect of Hot Water Extraction on Contact Angle of Octomeles sumatrana and Duabanga moluccana Woods and Its Correlation to the Extractive Content and Anatomical Structure: Pengaruh Hot Water Extraction terhadap Sudut Kontak Octomeles sumatrana dan Duabanga moluccana dan Kaitannya terhadap Zat Ekstraktif dan Struktur Anatomi Kayu. PERENNIAL, v. 21, n. 2, p. 61–70, 31 Oct.2025.