Pungitore, C., J. Padrón, L. Leon, C. Garcí­a, G. Ciuffo, V. Martin, and C. Tonn. “Inhibition of DNA Topoisomerase I and Growth Inhibition of Human Cancer Cell Lines by an Oleanane from Junellia Aspera (verbenaceae)”. Cellular and Molecular Biology, vol. 53, no. 3, May 2007, pp. 13-17, https://cellmolbiol.org/index.php/CMB/article/view/1121.