Velasquez-Melendez, Gustavo, et al. “ Relationship Between Acute Diarrhoea and Low Plasma Levels of Vitamin A and Retinol Binding Protein ”. Revista Do Instituto De Medicina Tropical De São Paulo, vol. 38, no. 5, Oct. 1996, pp. 365-70, https://revistas.usp.br/rimtsp/article/view/29402.