Singelyn, F., Contreras, V., Lefebvre, B., & Gouverneur, JM. (1993). Adding Sufentanyl To Mepivacaine Results in Faster But Not Prolonged Anesthesia and Analgesia After Brachial-plexus Blockade. Anesthesiology, 79(3A), A832-A832. (Original work published 1993)