Hellers, B. G. (1973). Columns with and without tensile strength: An extension of theories used for the comparison of deflections, rotations, stresses and stability. National Swedish Institute for Building Research.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Hellers, Bo Göran. Columns with and Without Tensile Strength: An Extension of Theories Used for the Comparison of Deflections, Rotations, Stresses and Stability. Stockholm: National Swedish Institute for Building Research, 1973.
Trích dẫn kiểu MLA (xuất bản lần thứ 8)Hellers, Bo Göran. Columns with and Without Tensile Strength: An Extension of Theories Used for the Comparison of Deflections, Rotations, Stresses and Stability. National Swedish Institute for Building Research, 1973.
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