Ashby, M & Maidment, J. (2005). Introducing Phonetic Science. Cambridge: Cambridge University Press.
Catford, J.C. (2001, 2nd ed). A Practical Introduction to Phonetics. Oxford: Oxford University Press.
Collins, B & Mees, I. (2013, 3rd ed). Practical Phonetics and Phonology. New York: Routledge.
Cruttenden, A. (2014, 8th ed). Gimson’s Pronunciation of English. Abingdon: Routledge.
Gick, B et al (2003). Articulatory Phonetics. Chichester: Blackwell Publishing.
Handbook of the International Phonetic Association. (1999). Cambridge: Cambridge University Press.
Haverhill J. (2015). An Ultrasound Analysis of Low Back Vowel Fronting in The Northern Cities Vowel Shift. In The Scottish Consortium for ICPhS 2015 (Ed.), Proceedings of the 18th International Congress of Phonetic Sciences. Glasgow, UK: the University of Glasgow. Paper number 0921.
Knight, D (2012). Speaking with Skill. London: Bloomsbury Publishing Plc.
Ladefoged, P & Johnson, K. (2011, 6th ed). A Course in Phonetics. Canada: Wadsworth Cengage Learning.
Ladefoged, P & Ferrari Disner, S. (2012, 3rd ed). Vowels And Consonants. Chichester: Blackwell Publishing Ltd.
Ladefoged, P. An academic life. Online.
Rogers, D & d’Arcangeli, L. The sound pattern of Standard Italian, as compared with the varieties spoken in Florence, Milan and Rome. Journal of the International Phonetic Association. 35, 2 (2005): pp.131-151. Online.
Sturtevant, E. H. Reviewed Work: The Vowel: Its Physiological Mechanism as Shown by the X-Ray by G. Oscar Russell. Language. 5, 1 (1929): pp. 33-36. Online.