Muhammad Muhayyidin, Ahmad Hafizan, et al. “Tannin Extraction from Bark of Rhizophora Mucronata Using Soxhlet and Boiling Techniques”. International Journal on Advanced Science, Engineering and Information Technology, vol. 8, no. 6, Dec. 2018, pp. 2525-30, doi:10.18517/ijaseit.8.6.3899.