WALKER, E; ELSWORTH, S. 2000. Grammar practice for pre-intermediate students: With key. 7th impression. Harlow, Essex: Longman/Pearson Education Limited.
APA (7th ed.) CitationWalker, E., & Elsworth, S. (2000). Grammar practice for pre-intermediate students: With key (7th impression.). Longman/Pearson Education Limited.
Chicago Style (17th ed.) CitationWalker, Elaine, and Steve Elsworth. Grammar Practice for Pre-intermediate Students: With Key. 7th impression. Harlow, Essex: Longman/Pearson Education Limited, 2000.
MLA (9th ed.) CitationWalker, Elaine, and Steve Elsworth. Grammar Practice for Pre-intermediate Students: With Key. 7th impression. Longman/Pearson Education Limited, 2000.
