1. ?AD-Merkblatt HP 7/1? in Vereinigung der Technischen Uberwachungsvereine e. V in Essen, April 1975.
2. ASME Boiler and Pressure Vessel Code, Section VIII, Parts I and II, in Specification for Unfired Fusion Welded Pressure Vessels, 1974.
3. BS 5500 (1976). BS 806 (1975). BS 3059 (1968) in British Standards Institutions.
4. Construction of Pressure Vessels JIS B 8243, in Japanese Industrial Standard (1977), Section 12.6.
5. Heat treatment of unalloyed and low-alloy steel W0701/75-12, in Dienst voor het Stoomwezen, The Hague.