Chicaíza-Becerra, Liliana Alejandra, and Mario García-Molina. “From the EQ-5D Tool and the Visual Analog Scale to Happiness”. Colombian Journal of Anesthesiology, vol. 42, no. 1, Jan. 2014, pp. 1–3, https://www.revcolanest.com.co/index.php/rca/article/view/614.