http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
TCVN 8 -50: 2005. ISO 128 -50: 2001. Bản vẽ kỹ thuật- Nguyên tắc chung về biểu diễn. Phần 50: Quy ước cơ bản về biểu diễn các diện tích trên mặt cắt và hình cắt