Mardia T. El Sayed, Kazem Mahmoud, and Andreas Hilgeroth. 2014. “Novel Aspects of Domino Reaction of Indoles With Homo- Phthalaldehyde and Tere-Phthalaldehyde”. Global Journal of Science Frontier Research 14 (B6):15-21. https://journalofscience.org/index.php/GJSFR/article/view/1332.