Al-Sabha, T., and I. A. Hamody. “Spectrophotometric Determination of Trimethoprim Using 2,4-Dinitro-1-Fluorobenzene Reagent”. Journal of Education and Science (JES), vol. 24, no. 2, Nov. 1999, pp. 1-11, doi:10.33899/edusj.1999.58728.