N. Kumar, C. Lal, B. Singh, and A. K. Patel, “Synthesis and Biological Activities of Some Novel Spiro Heterocyclic Pyrrolizidine Derivatives of 11H-indeno[1,2-b]quinoxaline through 1,3-Dipolar Cycloaddition”, ajc, vol. 32, no. 5, pp. 1255–1258, Apr. 2020.