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.

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.

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.