APA (7th ed.) Citation

Brook, G. L. (1973). Varieties of English / (by) G.L. Brook. Macmillan.

Chicago Style (17th ed.) Citation

Brook, G. L. Varieties of English / (by) G.L. Brook. London: Macmillan, 1973.

MLA (9th ed.) Citation

Brook, G. L. Varieties of English / (by) G.L. Brook. Macmillan, 1973.

Warning: These citations may not always be 100% accurate.