Sousa, Aurea, Licinio Tomas, Osvaldo Silva, and Helena Bacelar-Nicolau. “SYMBOLIC DATA ANALYSIS FOR THE ASSESSMENT OF USER SATISFACTION: AN APPLICATION TO READING ROOMS SERVICES”. European Scientific Journal, ESJ 9, no. 21 (July 12, 2013). Accessed November 28, 2021. https://eujournal.org/index.php/esj/article/view/1429.