Sharma, Varun, et al. “Crystallographic Structure, Activity Prediction, and Hydrogen Bonding Analysis of Some CSD-Based 3,3’-Bis-Indole Derivatives: A Review”. European Journal of Chemistry, vol. 12, no. 4, Dec. 2021, pp. 493-01, doi:10.5155/eurjchem.12.4.493-501.2145.