Nielsen, Kjetil, Gabrielle Hansen, and John Stav. “Teaching With Student Response Systems (SRS): Teacher-Centric Aspects That Can Negatively Affect students’ Experience of Using SRS”. Research in Learning Technology 210 (June 11, 2013). Accessed August 24, 2019. https://journal.alt.ac.uk/index.php/rlt/article/view/1340.