Arif, Md. Khaja, et al. “Synthesis of Chromeno Pyrano-Quinolines via Tandem Approach Involving Michael Addition-Cyclization Catalyzed by L-Proline Cu(II)”. Asian Journal of Chemistry, vol. 37, no. 2, Jan. 2025, pp. 473-8, doi:10.14233/ajchem.2025.33209.