Walker, E., Elsworth, S., & Nguyễn Văn Phước. (2001). Grammar practice for upper intermediate students (New ed.). Tp.HCM: Nxb Trẻ.
استشهاد بنمط شيكاغوWalker, Elaine., Steve Elsworth, و Nguyễn Văn Phước. Grammar Practice for Upper Intermediate Students. New ed. Tp.HCM: Nxb Trẻ, 2001.
MLA استشهادWalker, Elaine., Steve Elsworth, و Nguyễn Văn Phước. Grammar Practice for Upper Intermediate Students. New ed. Tp.HCM: Nxb Trẻ, 2001.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.