1. API STANDARD 1104: Welding of pipeline and related facilities. 20 ed.; 2005.
2. ASME SECTION IX: Qualification standard for welding and brazing procedures, welders, brazers, and welding and brazing operators; 2002.
3. DNV-OS-F101: Submarine pipeline systems; 2000.
4. IPS-C-PI-270(2): Construction standard for welding of transportation pipeline, 2009.
5. GB Standard 50236–97, GB, China; 1999.