http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Bài tập tiếng Anh dùng kèm English 11
Lê Ngọc Bửu; Biên soạn: Trần Văn Khánh
english language - study and teaching ( secondary ),english langugae - problems, exercises ( secondary )