Schwartz, Geoffrey, and Ewelina Wojtkowiak. “Asymmetrical Equivalence Classification – Cluster Affrication Vs. Lenis Stops in the Speech of Polish Learners of English”. Research in Language 21, no. 4 (December 28, 2023): 421–442. Accessed May 20, 2024. https://www.czasopisma.uni.lodz.pl/research/article/view/21589.