“…Within the subregular hierarchy of formal languages, the class of Strictly Local languages, which model local phonotactic restrictions (Mc-Naughton and Papert, 1971;Rogers and Pullum, 2011;Rogers et al, 2013) have been extended to incorporate the notion of a tier, resulting in the class of Tier-based Strictly Local (TSL) languages (Heinz et al, 2011). Likewise, the Input Strictly Local (ISL) and Output Strictly Local (OSL) functions-which characterize locallybounded phonological processes as subregular maps (Chandlee, 2014;Chandlee et al, 2014Chandlee et al, , 2015-have been generalized to the classes of Input Tier-based Strictly Local (ITSL) and Output Tier-based Strictly Local (OTSL) functions in order to account for non-local phonological processes (Burness and McMullin, 2019;Hao and Andersson, 2019;Hao and Bowers, 2019).…”