APA (7th ed.) Citation

Gass, S. M., & Lefkoowitz, N. (1995). Varieties of English. Univ. of Michigan Pr.

Chicago Style (17th ed.) Citation

Gass, Susan M., and Natalie Lefkoowitz. Varieties of English. Ann Arbor: Univ. of Michigan Pr, 1995.

MLA (9th ed.) Citation

Gass, Susan M., and Natalie Lefkoowitz. Varieties of English. Univ. of Michigan Pr, 1995.

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