Nief, O. A. “Synthesis and Identification of Heterocyclic Compounds (Oxazepine, Tetrazole) Derived from Benzidine As Photostabilizing for Poly Vinyl Chloride”. Al-Mustansiriyah Journal of Science, vol. 28, no. 2, Apr. 2018, pp. 108-1, doi:10.23851/mjs.v28i2.521.