Biographical note

David Singleton is Fellow Emeritus, Trinity College Dublin, Ireland, Professor  Emeritus, University of Pannonia, Hungary and Professor, University of Applied Sciences, Konin, Poland. He is the author of numerous monographs and textbooks, including Key Topics in Second Language Acquisition (2014, with Vivian Cook, Multilingual Matters) and Beyond Age Effects in Instructional L2 Learning (2017, with Simone Pfenninger, Multilingual Matters). Simone E. Pfenninger is Assistant Professor at the University of Salzburg. Her principal research areas are multilingualism, psycholinguistics and individual differences (e.g. the age factor) in SLA, especially in regard to quantitative approaches and statistical methods and techniques for language application in education. Recent books include Beyond Age Effects in Instructional L2 Learning: Revisiting the Age Factor (2017, co-authored, Multilingual Matter), The Changing English Language: Psycholinguistic Perspectives (2017, co-edited, CUP), and Future Research Directions for Applied Linguistics (2017, co-edited, Multilingual Matter). She is co-editor of the Second Language Acquisition book series for Multilingual Matters.