Ammar A. Dawood, Emaad M. Awsaj and Alaa S. Ateaa 2023. The preparation of " salicylic acid azo 2,2,4,4 tetrahydroxybenzophenon" dye using Dowex in the acidic form as a catalyst. Tikrit Journal of Pure Science. 22, 7 (Feb. 2023), 103–108. DOI:https://doi.org/10.25130/tjps.v22i7.839.