Castro, Danilo, et al. “Evaluation of the Utility of Unidirectional Doppler: Effect in the Study of Arteriopathies of the Leg”. Cirugía Del Uruguay, vol. 54, no. 6, Apr. 1984, pp. 424-9, https://replica-revista.scu.org.uy/index.php/cir_urug/article/view/3629.