1. 5) TIMOSHENKO S. Theory of Plates and Shells.. McGraw-Hill Book Co.. (1940)
2. 6) ROARK R. J. Formulas for Stress and Strain. McGraw-Hill Book Co.. (1954)
3. 12) GIBSTEIN M. B. Static Strength of Tubular Joints. Det Norske Veritas Report. (1973)
4. 14) POPOV V. S. Research into The Strength of The Joints between The Lattice Members and Chords in Tubular Welded Structures. Aut. Svarkea. (1972) vol.3, p.30-31.
5. 15) SAMMET H. Die Festigkeit Knotenblechloser Rohrverbindungen im Stahlbau. Schweisstechnik. (1963) vol.13, no.11, p.481-486.