1. 1) R. BRUSCATO : Welding J. 49(1970) 4, p. 148 S
2. 2) R. A. SWIFT and H. C. ROGERS : Welding J. Research Supplement, 52 (1973) 4, p. 145 S
3. 3) C. D. CLAUSER, L. G. EMMER, A. W. PENSE, and R. D. STOUT : "Paper for presentation of a session on Refining Piping during the 37 th Midyear Meeting of API", May, 11 (1972)
4. 4) R. A. SWIFT and J. A. GULYA : Welding J. Research Supplement, 52 (1973) 2, p. 57 S
5. 6) K. MIYANO : Paper for presentation of the API Task Group Meeting in Chicago Feb. 20/21 (1974)