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7British energy generation ltd.. R6: Assessment of the integrity of structures containing defects [S]. revision 4. [s. l. ]: British energy generation ltd. , 2001.
8Raju I S, Newman J C. Stress-intensity factors for internal and external surface cracks in cylindrical vessels[J]. J. pres. yes. technol. ,1982,104:293--298.
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10Appendix C. API Recommended Practice 579[S]. [s. l. ] :American petroleum institute, 2000.
