Swan, M., & Walter, C. (1997). How english works: A grammar practice book with answers. Oxford: Oxford Univ. Press.
Chicago-стиль цитированияSwan, Michael, và Catherine Walter. How English Works: A Grammar Practice Book With Answers. Oxford: Oxford Univ. Press, 1997.
MLA-цитированиеSwan, Michael, và Catherine Walter. How English Works: A Grammar Practice Book With Answers. Oxford: Oxford Univ. Press, 1997.
Предупреждение: эти цитированмия не могут быть всегда правильны на 100%.