1999NF A04-315-4:1999 Non-destructive testing of steel forgings. Part 4 : ultrasonic testing of austenitic and austenitic-ferritic stainless steel forgings.
1991NF A04-310:1991 AUSTENITIC AND AUSTENO-FERRITIC STAINLESS STEEL FORGINGS. ULTRASONIC TESTING. INSPECTION METHODS. LIMITS OF ACCEPTANCE.