•   DIN EN ISO 6988 Metallic and other inorganic coatings - Test with sulfur dioxide with general moisture condensation, March 1997.
•	DIN 50018 testing in an alternating condensation climate with an atmosphere containing sulfur dioxide, June 1997.
•	The importance of corrosion test procedures with special consideration of the SO test according to DIN 50018, Wilhelm Kesternich, published in Materials and Corrosion Volume 16, Issue 3, pages 193-201, March 1965.