“…Overall, prior research (Ainsworth, 1999; De Bock et al, 2017; Duval, 2006; Goldin, 2003; Hurst et al, 2020; Lesh, 1981; Lesh et al, 1987) revealed the importance of external representations for mathematical learning, but most of these previous studies focused on a conventional learning setting. Recently, research on the field of external representations for mathematical problem solving in DGBL is increasing (Bullock et al, 2021; Duval, 2017; Hung et al, 2014; Moyer-Packenham et al, 2019; 2021), but still scarce.…”