Swan, M., & Walter, C. How english works: A grammar practice book with answers.
Čikaški stil citiranja (17. izdanje)Swan, Michael, i Catherine Walter. How English Works: A Grammar Practice Book with Answers.
MLA način citiranja (8. izdanje)Swan, Michael, i Catherine Walter. How English Works: A Grammar Practice Book with Answers.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.