Pereira da Cruz, J.G. 2008. <b>The effect of morphine on vagal inhibition of the heart: demonstration of dual atrioventricular nodal pathways</b&gt; - DOI: 10.4025/actascihealthsci.v28i2.1102. Acta Scientiarum. Health Sciences. 28, 2 (Mar. 2008), 171-174. DOI:https://doi.org/10.4025/actascihealthsci.v28i2.1102.