Pungitore, C.; Padrón, J.; Leon, L.; Garcí­a, C.; Ciuffo, G.; Martin, V.; Tonn, C. Inhibition of DNA Topoisomerase I and Growth Inhibition of Human Cancer Cell Lines by an Oleanane from Junellia Aspera (verbenaceae). Cell Mol Biol (Noisy-le-grand) 2007, 53, 13-17.