Aguirre-Ospina, Oscar David, Julián Felipe González-Maldonado, and Ángela María Ríos-Medina. 2015. “Ergonomics in Ultrasound-Guided Nerve Blocks”. Colombian Journal of Anesthesiology 43 (4):331–339. https://www.revcolanest.com.co/index.php/rca/article/view/356.