Sáenz R., J.A. and Nassar C., M. 1970. Phytochemical screening of Costa Rican plants: Alkaloid analysis. IV. Revista de Biología Tropical. 18, 1-2 (Dec. 1970), 129–138. DOI:https://doi.org/10.15517/rev.biol.trop. v18i1-2.28091.