1. Faculty of Forestry and Environment, IPB University (Bogor Agricultural University), Dramaga, Bogor 16680, West Java, Indonesia
2. Faculty of Engineering, Pakuan University, Jl. Pakuan, Tegallega, Bogor 16129, West Java, Indonesia
3. Faculty of Forestry, Universitas Sumatera Utara, Deli Serdang 20353, North Sumatra, Indonesia