Sáenz R., J. A., & Nassar C., M. (1970). Phytochemical screening of Costa Rican plants: Alkaloid analysis. IV. Revista De Biología Tropical, 18(1-2), 129–138. https://doi.org/10.15517/rev.biol.trop.v18i1-2.28091
A total of 72 species of Costa Rican plants were tested for their alkaloid content in both acid and alkaline layers; 16 of them are reported for the first time as containing alkaloids.