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2. 2) AISC: Load and resistance factor design, 2nd edition, Manual of steel construction, American Institute of Steel Construction, Chicago, 1994.
3. 3) Galambos, T. V.: Structural Members and Frames, Englewood Cliffs, N. J., 1968.
4. 4) Yura, J. A.: The effective length of columns in unbraced frames, AISC Engineering Journal, Vol. 8, No. 2, pp. 37-42, Apr., 1971.
5. 5) Nishino, F., Miki, C. and Suzuki, A: Background of revision of specifications for highway bridges (Japan road association)-design of rigid frames, Bridge and Foundation Engineering, Vol. 15, No. 10, pp. 10-13, 1981-10 (in Japanese).