Analysis of customer satisfaction using surveys with open questions. - Amelio Medina-Merodio, José; de Pablos-Heredero, Carmen; Lourdes Jiménez-Rodríguez, María; de Marcos-Ortega, Luis; Barchino-Plata, Roberto; Rodríguez-García, Daniel; Gómez-Aguado, Daniel (Dyna (0012-7353), 2014)