Machado-Silva, José Roberto, et al. “ Schistosoma Mansoni Sambon, 1907: Comparative Morphologica Studies of Some Brazilian Strains ”. Revista Do Instituto De Medicina Tropical De São Paulo, vol. 37, no. 5, Oct. 1995, pp. 441-7, https://www.revistas.usp.br/rimtsp/article/view/29305.