http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Tiêu chuẩn Việt Nam: Ổ lăn. Phương pháp tính tần số quay giới hạn: TCVN 4172-85
Ủy ban khoa học kỹ thuật nhà nước
Tiêu chuẩn này áp dụng cho ổ bi và ổ dũa công dụng chung, chế tạo theo TCVN 1484-85 và làm việc ở nhiệt độ không vượt quá 100 độ C
Bộ cơ khí và luyện kim, Viện nghiên cứu máy