“…Certainly, all reviews need to stop at a certain moment, and, in consequence, this might leave aside studies in the process of being published. To the knowledge of the author, at least a couple of studies are about to be published early in 2020 that, potentially, could have been included in this review: Appelgate et al (2020) and Hervas et al (2020). As for the initial year, 1997 was set because, even if according to a great number of previous literature (e.g., Bjuland & Mosvold, 2015; Fujii, 2016; Lewis, 2009; Shimizu & Chino, 2015; Takahashi & McDougal, 2016), the international popularization of LS took place after the studies of Stigler and Hiebert (1999) and Yoshida (1999), we find earlier literature around that date (e.g., Lewis & Tsuchida, 1997).…”