1. Geiger EL (2000) Chapter A2: Piping Components. In: Nayyar ML (ed) Piping Handbook 7th ed, McGraw-Hill, New York, NY, A.53‒A.123
2. ASME B16.9–2018: Factory-Made Wrought Buttwelding Fittings (2018) American Society of Mechanical Engineers, New York, NY
3. MSS SP-75–2019: High-Strength, Wrought, Butt-Welding Fittings (2019) Manufacturers Standardization Society, Vienna, VA
4. MSS SP-43–2019: Wrought and fabricated butt-welding fittings for low pressure. Corrosion Resistant Applications. Manufacturers Standardization Society, Vienna, VA, 2019
5. Miller G (2003) Tube forming processes: a comprehensive guide. Society of Manufacturing Engineers (SME), Dearborn, MI, pp 129‒130