Carvalhinhos, A., Freire, A., de Oliveira, A.G., Lopes, M.J., Novais, L., Veloso, J. and Correia, J.P. 1986. The lower esophageal sphincter and gastroesophageal competence. Acta Médica Portuguesa. 7, 2 (Apr. 1986), 75–81. DOI:https://doi.org/10.20344/amp.3598.