M. EL-GENDY, A., et al. “Preparation and Some Reactions of 1,4-Diaryl-1,3-Butadiene-2,3-Dicarboxaldebyde”. Asian Journal of Chemistry, vol. 2, no. 1, June 2010, pp. 91-95, https://asianpubs.org/index.php/ajchem/article/view/25293.