Halliday, M A K.1968. The Users and Uses of Language. In Joshua A. Fishman, ed. Readings in the Sociology of Language. The Hague: Mouton and Co.
2.
Shuy, Roger W.1972. Speech Differences and Teaching Strategies: How Different is Enough? In David L Shores, ed. Contemporary English : Change and Variation. Philadelphia: J B Lippincott Co.
3.
Wijk, A.1973. Regularized English. In W Haas, ed. Alphabets for English. 1969. Manchester University Press.