“PHYSICAL TESTS OF ORGANIC INK BASED ON GUM ARABIC, GAMBIER, AND JANGGELAN LEAVES”. Al-Fiziya: Journal of Materials Science, Geophysics, Instrumentation and Theoretical Physics, vol. 7, no. 1, Jan. 2025, pp. 54-61, https://doi.org/10.15408/fiziya.v7i1.40521.