An introduction to formal languages and automata (5th ed.)by Peter Linz, 2011
English language teaching today: linking theory and practiceby Willy A. Renandya & Handoyo Puji Widodo (editors), 2016
Second language acquisition and task-based language teachingby Mike Long, 2014
Theory of language: the representational function of languageby Karl Buhler, 2011