H. Hussein, Falah, et al. “Determination of Benzo[a]anthracene in Surface Water of Shatt Al-Hilla River by Solid Phase Extraction and High Performance Liquid Chromatography”. Asian Journal of Chemistry, vol. 26, no. 9, Apr. 2014, pp. 2781-3, doi:10.14233/ajchem.2014.16801.