Gálvez, R., J. Caballero, M. Atero, S. Ruiz, and J. Romero. 2004. “Venlafaxine Extended Release for the Treatment of Chronic Pain. A Series of 50 Cases”. Actas Españolas De Psiquiatría 32 (2):92-97. https://actaspsiquiatria.es/index.php/actas/article/view/1152.