Kossoff, P., Hernández, F., Vekoh-Pardo, M. V., & Zimmerman, M. (1989). Urban helminthiasis in two socioeconomically distinct Costa Rican communities. Revista De Biología Tropical, 37(2), 181–186. Retrieved from https://revistas.ucr.ac.cr/index.php/rbt/article/view/23571