Swan, M., & Walter-Laager, C. (2007). How English works: A grammar practice book ; with answers (1. publ., 18. impr.). Oxford Univ. Press.
Chicago Style (17th ed.) CitationSwan, Michael, and Catherine Walter-Laager. How English Works: A Grammar Practice Book ; with Answers. 1. publ., 18. impr. Oxford [u.a.]: Oxford Univ. Press, 2007.
MLA (9th ed.) CitationSwan, Michael, and Catherine Walter-Laager. How English Works: A Grammar Practice Book ; with Answers. 1. publ., 18. impr. Oxford Univ. Press, 2007.
Warning: These citations may not always be 100% accurate.